My anger is destroying my relationship with my girlfriend

This is the third fight this week I've had with my girlfriend of over a year, i feel horrible, i feel so disappointed and angry at myself for blowing up on her .. all because she didn't want to have sex with me when i wanted (our fights are not about sex normally). Overtime whenever we get into a fight i make it worse by not giving her the space she asks for , i also make things worse by getting physical with her by either taking away whatever she has in her hand like her laptop or phone because i feel like she's just ignoring me, and she is for a good reason. I can't help but to lash out on her, i literally go from 0 to 100 in .5 seconds its scary honestly... ever since i can remember I've always been angry as a kid as a teen and now as a young adult. I was a hard core drug user in the past but I've been clean for a while now (almost 2 years i believe) I also have gone to rehab i was diagnosed there with bipolar disorder and chronic depression. I'm tired of putting my girlfriend through this its not her fault and she does not deserve any of it. I love her very much she's the first woman that i have ever loved there is nothing that i wouldn't do for her , i would never hurt her though i do emotionally because of my deep anger issues. I do get angry to the point where i want to hurt myself and hurt others (not my girlfriend) and sometimes it gets so intense (anger) i can't help but to think and picture myself killing someone and feeling like a million bucks afterwards it gives me satisfaction at that moment, but i do come to my senses and say no to myself and i quickly change subjects in my head. I also go from having my voice raised to actually full on screaming at her, i can't begin to describe how much anger and hate i feel towards myself during and after our fights, its like I'm literally going to explode and theres no going back... I want to be normal not just for myself but for my girlfriend. She means the world to me i don't know what i would do if i really lost her for good because of my anger issues. PLEASE anyone who reads this i need advice before its too late. fyi i want to go to therapy i know i need it. sorry for the crappy grammar and or spelling.