To shy to have sex

When I was younger I was sexually molested and raped. I kept it to myself for so many years that when I was in high school I tried to commit suicide. I’ve dealt with a lot of the issues and ptsd that comes with rape. One thing I can’t seem to get over is the fear of sex. I feel ready and I want to but every time I get close I psych myself out. I’ve been talking to this guy for a month or two. He wants to hook up but since it would be my first time since I was raped I don’t know how to tell him it’s my first time and it would need to be slow. He’s so much more experienced that I feel sort of ashamed! Help! What do I do?