Stressed family relations, who is to blame?

I am a marine corps vet 06-07 OEF II. Ever since I got back I have had less and less contact with my family. It concerns me enough to write about it to you fine folks but not enough to seek professional help or intervention.

A lot of things changed when I got back. My dad got remarried and bought a house, my sister got accidentally pregnant by a drug dealing thug, my mom turned into a religious nutjob and got remarried. This is what I used to consider my nuclear family. I have two step siblings which I will get to later.

Since getting back I've become increasingly less tolerant of people to the point that I've pushed away about 80% of my friends (either they are creationists or have no integrity). This has bled over to family ties. Lately I've become very hypercritical about a lot of things and have spent a great deal of time analyzing things that have happened in the past. Up to this point for whatever reason they have never bothered me but now I use it as ammunition to fuel my justification of considering just cutting ties altogether.

My father - a racist, sexist, alcoholic and abusive man. My sister and I are adopted, we are asian and have white parents. My father is very racist towards blacks and mexicans. I've tried to point out that if you are racist towards one group it is just as offensive to me b/c it's that same ignorance that I have to deal with from time to time. He just laughs like it's no big deal. I know he's cheated on my mom when they were married. He used to bring us kids out to the boondocks once in a while to meet a woman (who used to be a former student of his). it didn't don on me till recently that he was having an affair after thinking about "why the hell would he drive all the way out there to meet some woman I've never met?". He has a short short temper and verbally abused us, lots of yelling and swearing. He's also hit me on numerous occasions for rediculous things (when I was 7 was playing hide and seek with sister. dad wanted to leave and get us in the car but we kept running around. he waits behind a door, waits for me to walk past it and slams me in the face with his fist hard enough to flatten me on the ground.) He is also a union lawyer for the police in a major metropolitan area. He is responsible to getting thousands of crooked cops back on the street throughout his career. He has always used money as leverage on us kids. I used to think I loved him, but I realize now how much I hate him.

My biological sister - we've always been very close until I was deployed. while I was deployed my sister was inpregnated by some asshole drug dealer. my sister dates black guys exclusively. my dad wonders why and I tell him b/c he is such a racist, he of course laughs it off and gets pissed at me. she tells me this while I'm deployed! like I didn't need more stress. I get back and she is defaulting on a car lease. I take it over as a favor and since I didn't have a car since I just got back from deployment it was a win-win. 6 months down the road she demands the car back (agreement was I finish out the lease terms). in a fervent feverish anger I had never seen from her before. I just give her the damn car back and buy a used car. drug dealer baby daddy takes car on suspended liscence joyride. gets pulled over flees from police - 8 months state prison. dude gets out. sister's ATM card gets stolen. she accuses me of stealing over $1000 from her card. presses formal police charges. during investigation they find out that it was her baby daddy on the ATM recorder taking out money. they get married. have two more kids. both become religious nuts (his parents are religious). wants to homeschool kids on creationism. I have arguments and thoughts. Wash my hands of this too?

My mother - forced me to go to church despite me protesting it wildly as a child. I finally had to put my foot down when I was 16 and said NO MORE!! since then I haven't gone to church and I'm 31 now. after age 10 she resented me a great deal b/c of my resistance to religion. she played favorites and made it obvious. whenever i managed to save more than $100 as a kid she would force me to spend it on my own meals and shampoo and shit like that. never telling me to keep saving. teaching me, if you save money I make you buy things you normally get for free as a kid. dad and mom get divorced at 16 she moves away. at that time we were not very fond of eachother. since then awkward convos on the phone on birthdays and holidays. she always rushes me off the phone. she never calls. I decided to stop too. haven't talked to her in years.

step sister - the shining star of the family, a doctorate in OT, professor at med school - know it all bitch. last time I see her we visit her house for thanksgiving - 6 day trip. i like to be good guest. I try helping around the house, doing dishes, cleaning up, ect. everything I do is not good enough. constant complaining. never went back. see her sometimes throughout the year - relationship is stressed, not much talking. we don't talk on the phone at all.

step brother - this fuckhead really screwed me up as a kid. granted he was physically abused by his nanny who used to beat him with a wooden paddle but no excuse for his behavior. he is a 50 year old unemployed degenerate. fired from over 30 different job in the span of a decade. he is also the most prolific compulsive liar I have ever met. when I was a kid and he was in highschool he would drink in the car when dropping me off at my mother's house. when I was a kid and would ask him questions of curiosity he would intentionally distort the truth to distort my understanding of basic things in a effort to derail my mental development? now that we're both grown ass men he lies.. he lies all the time to everyone not just me. everyone in family knows he is a compulsive liar, we have had lengthy discussions as a family about it. he lies about me all the time. i have a medical grow. he lies to my father saying I grow illegally and I have over a 100 plants. father comes over furious only to find that I am legal and only have 8 plants. step brother lies about god knows what else. this stems from the fact that despite my father's abuse, I am his favorite child and he has made no effort to disguise this. this makes my step brother insanely jealous even though he has done nothing in his life to grant such adoration.

Is it any wonder I avoid family holidays at all costs? or am I a intolerant son of a bitch that needs to grow up?

I have a deep desire to go back to my youth when certain aunts and uncles were still married
grandparents were still alive and I felt normal. However those things are no longer as they were and they never will
be again. Find ways to enjoy today. your future is not somewhere in the past. Best of luck its a tough awareness
but you have made it this far. Enjoy the memories