I'm going to use my favourite kind of analogy to start off with; an optical illusion. Look at the grid below; the square marked A is dark, and the square marked B is light, correct?
In actuality, they are both the same shade of grey- the effects of boundaries and perceived light/shadow just makes one look dark and the other light.
Such is the way many things in life seem- polar opposites are really different manifestations on the same plane of error; they just depend on the boundaries and perceived light/shadow in life. Just as Alan Watts said, "Every explicit duality is an implicit unity". For example, someone morbidly overweight who later becomes extremely 'shredded' (brah) still has that plane of error where food and eating habits relate to feelings of control, self-efficacy and self-worth. The only difference is their perceived self worth (shadow/light), and their environment (boundaries).
In fact, this is how we as people essentially navigate through our world; we let our past experiences delineate these different planes with which we perceive and interact with our environment.
Think of your inner self as a tiny sphere made of some really sensitive and unexposed material (in a similar sense to how virgin skin under a wound is yet to be exposed to the seasons, and is really sensitive to touch). This inner sphere represents your self concept, as shaped by your experiences, or 'personal truths'. For example, if you grew up feeling misunderstood, your self concept might involve feelings of being an outlier/outsider.
Then imagine an outer shell surrounding this tiny sphere; this is what you project and is the idea of yourself that you consciously convey to the world. These ideas are spectral points on these different planes delineated by your early experiences; for instance, with the previous example of being an outlier, you might project an anti-conformist character, or someone who completely fits within the norm/fashion. Each of these manifestations are just vehicles for projecting self-worth or inner confidence on the same plane of 'fitting in'. They are basically forms of armour convincing your inner self that you have value (either you fit in, or you are proud of not fitting in). The truth is that these polarities just show that subconsciously, an issue does exist related to accepting yourself and how you are received by your environment.
Still with me? So basically, your identity is a little vulnerable ball surrounded by a ball of armour with a lot of spokes.
[How to hate]
Of course, realistically we cannot cover all our insecurities, and there have to be some spots left vulnerable and unprotected. These are our weak points, the aspects of us that evoke an innate knee-jerk reaction because they hit a little too close to home. Think of the times you've had a reflex defence mechanism and reacted sensitively to a cheap shot.
Sadly, what happens a lot is that in relationships, we look to a partner to be a bandaid for that under-exposed inner shell. They can act as a bandaid by:
1. Being representative of the ideals you want to project (essentially a trophy), so that by means of association, you too embody these ideals 2. Fuelling your ego. For example, by constantly giving you reinforcement and making you feel validated
Too many times I have thought someone was genuinely interested in me, only to find out I was just seen as a functional bandaid.
What is wrong with this?
1. It dehumanises your partner. They are just serving you like a commodity; and once they become a real, fallible human with flaws, they will no longer embody a representative of your projections. Once they no longer serve your ego's desires, they will drop in value (like how people randomly 'fall out of infatuation' for someone).
What's worse is that you may continue to see them as a two dimentional entity, and not treat them as a real person. For example, you may value their success (as a state, something you can associate with) and encourage it superficially, but not their actual work as a trait characteristic, and leave them feeling unsupported or discouraged.
2. When the fuel of reinforcement runs out, it can activate defence mechanisms from your ego e.g. being territorial of your partner, because they are the validation you need to complete your self concept.
Just as bad, you are vulnerable to becoming extremely emotionally unbalanced e.g. if they hit a nerve on your weak spot, you will lash out at them the most because that is where you are most sensitive; imagine your bandaid flying off and being stabbed right in the previously unexposed, open wound.
These kind of things lead to codependence. Rather than looking at who is in front of you and the person that they are/your association with each other, you are looking at their ability to evoke certain highs or feelings within you, and just like with drugs/addictions, that can unleash disproportionate primally aggressive withdrawal reactions.
[How to love]
Rather than try to cover this inner shell, we need to free it. Think of that virgin skin under the bandaid. Once the wound is closed, it has to bare itself and be weathered by the environment in order to become resilient enough to be exposed to the world on its own. To be resilient, we have to recognise that these planes we use to form our self concept and shape our perceived individual identity are just boundaries and shadows from our own past experiences. These experiences are just that, experiences; our personal truths, they are not universal. For example, an experience with poor self concept while you were poor does not mean that being affluent means you are a more worthy person. Holding onto that armour means that you are actually more vulnerable to having a weaker self concept, because it is dependent on your financial status.
If something negative happened to you before, why should you let that experience navigate the way you perceive your world now, and leave you at the mercy of your ego defence mechanisms? As Kahlil Gibran wrote, you 'need to break the chains which you at the dawn of your understanding have fastened around your noon hour'.
What is it but fragments of your own self you would discard that you may become free. If it is a despot you would dethrone, see first that his throne erected within you is destroyed. If it is a care you would cast off, that care has been chosen by you rather than imposed upon you. And if it is a fear you would dispel, the seat of that fear is in your heart and not in the hand of the feared
The more you let go and understand that your insecurities are a personal truth and not a universal truth, the more you prevent old experiences from impacting you in the present (in terms of the frameworks of mind with which you navigate your life). In turn, the less you feel the need to project certain images to justify yourself to others, and ultimately, the less you feel that you have to embody a certain ideal.
To go back to the original analogy, you let go of those spokes and armour and bare your inner self the same way that virgin skin gets thickened and more resilient; so that eventually, you won't need a bandaid. You get closer to becoming a complete person. Again, in the words of Kahlil Gibran,
'These things move within you as lights and shadows in pairs that cling. And when the shadow fades and is no more, the light that lingers becomes a shadow to another light. And thus your freedown when it loses its fetters becomes itself the fetter of a greater freedom'
Or in another sense, you rid yourself of these boundaries and shadows until the light and dark (as in the first illustration) both come closer to being the same shade of grey.
The more you are aware of your behaviours acting as masks or defence mechanisms, the more you will be able to recognise them in other people. The more you recognise these behaviours, the more you understand them as impersonal knee-jerk reactions and are able to disarm them rather than take offence. And eventually, the more compassionate you get, as you see yourself and your feelings of struggle/insecurity in other people's behaviours.
In this state, developing an affinity to someone will be genuine, and you will be able to disarm your own insecurities for their benefit, almost as though they are an extension of yourself; and this will be the ultimate display of true compassion.