Your internal and external lives are reflections of each other

Balanced internal life = Balanced external life.
Extreme internal life = Extreme external life.
Total internal awareness = Total external awareness
Internal extreme tunneled investments = External extreme tunneled investments.
Internal imbalances => reflected in the external as external imbalances.

Many extreme people view relationship as:
Conflict, Resistance, Strife, War, Violence, Pain.
The problem here is of degree and not of essence.
Like if I take a knife and ever so gently graze your skin, it will feel scintillating.
But if I do it with more force, it will cut the skin, sharply hurt, and leave a bruise.
So the problem in the latter case was simply the intensity.

In a world filled with limitation of various degrees,
If we try to do things with unlimited passion,
Either we will break or the thing will break.
Relationships are a limited possibility.
It has a certain place, a certain potential,
After which it will start to hurt and pain more and more.
This kind of violence can be addictive too,
Because it is controlled by you.
I would think this is a similar reason,
Why people cut themselves.
Because it is a pain that you can control and administer to yourself.
So by fighting with people, even if it hurts, you are controlling it.
And that might give a relief at a different level.
You could similarly, subject yourself to controlled mental pain too,
Say by researching on all sorts of painful topics,
Because then you are in control, you are subjecting yourself to it.

Generally what happens is a full cycle.
The person is maybe highly sensitive,
And was subjected to physical, relational, or mental violence.
Again the violence here is because of degree, and not essence.
Like if a blind person high five’s you on the nose by mistake.
High five is a cool thing, on your hands, but not on your nose.
So, then the person in later life,
In order to regain a sense of control,
May subject himself to the same abuse and recreate those feelings.
The huge difference in the second run of those feelings is that,
He inflicts them upon himself, so that gives him back his sense of control,
And allays the fear, paranoia, and expectation.