I feel like cutting him out of my life might help me in dealing with my issues (flashbacks, feelings of shame/violation, anger, interference in relationships with men and other areas as well), but I really do worry that if I stopped talking to him he might commit suicide or completely lose it.
You are the child. He is the adult. When you were a child in his care, he did not give you the care you were owed by him. Not only did he force you to take a level of responsibility you were not ready for, he also abused you in a way that you are still, as a 22-year-old, struggling with.
You say you think cutting contact with him would be helpful for you.
That is all you're responsible for.
Yourself.
You were taught early on that you had to be responsible for your dad. Because he wasn't responsible for himself. You know what my youngest said after I had divorced her father and she was with him part time? She said "Having two homes is crazy-making, and I wish I could just live in one place. But if I lived with Dad all the time I would miss you too much. And if I lived with you all the time, there would be nobody there to keep Dad safe when he drinks too much." She was 8 at the time.
I hear you saying the same thing. I hear you giving up what YOU need in order to take care of the needs of an adult who was abusive to you. So what if he loves you "the most" -- what does that mean? That he abused you LESS than he abused other people?
You have no responsibility to that man. You have no debt you need to pay to that man. You do have a responsibility to yourself to make the choices that are healthy for you.
I'm sorry if this sounds harsh but if your father is going to commit suicide, he will whether you're in contact with him or not. If he's going to fly off the handle, he will whether you're in contact with him or not. Those fears you have sound exactly like the fears an abuser implants in their victims to maintain control over them. They are not rational fears.