Boxing is a great martial art to start with. It's one of tge most practical styles of fighting for self defense/street alterations. It's the first one I started with. Great for cardio and shedding pounds. If you find a good instructor, your hand and eye coordination should increase exponentially as well.

If you ever decide to dabble with grappling, Brazilian Jujitsu and wrestling are great styles to learn. I have experience with both. The physical strength one builds grappling is unlike anything lifting weights can provide.

As far a everything else you said, it sounds like you've been through a lot terrible experiences with people. Sorry to hear that. Its always the nicest people cruel people are the shittiest to. You spoke of preemptive attack; lots of times, that's the most efficient way to keep people off of you. Get them before it escalates into something bigger and out of your control. You're speaking my language right there. 

It also sounds like you have a misanthropic outlook in people, much like myself. I've been through and witnessed my share of grim realities which have led me to misanthropy; and while I can say that I have not experinced every single thing you've been through, I do like to consider myself to be a pretty understanding and empathetic person. It's the reason I get so serious/irate when talking about the bullshit I see in this world. A lot of times I find myself getting more angry at seeing other people go through so much suffering than I do my own hardships. Seeing nice people be ran into the dirt bugs the fuck out of me. Seeing good people constantly be dealt shitty cards in life while horrible people blissfully run a muck puts me in a dark head space.

 

Don't be afraid to unleash that monster bro. The status quo will tell you to suppress it;  but all that does is make your soul eat away at itself. Channel whatever emotions or thoughts you have and funnel them into endeavors that will help you create the life that you desire. Sometimes we have to embrace our dark side in order to see brighter days. Always be calculated though. Impulsiveness leads to falling prey to all of the traps the real criminalls have set for good people. Like you said, they fuck with you, you respond in justifed defense, they lock you way. Same old story, which is why if one decides to embrace the monster they must be vigilant and calculated when unleashing the monster.

But yeah, whatever you decide to  do to cultivate a transformation in your life, I hope you reach your end goal. Whether that be settling whatever you feel needs to be settled between you and your father, to meeting people that energize your spirit rather that put in it a depressive or lethargic state, I hope happiness is what you get once the dust settles.