Intensely jealous relationship

I'm a 25 y/o female and I've been with my boyfriend for six months. We fell deeply, passionately in love with each other very quickly and have been inseparable since we met. We have a very affectionate, playful and loving relationship, and our sex life is incredible - by far the best sex that either of us have ever had. We can't get enough of each other.

The only problem is that we're both fkin psycho jealous! My boyfriend has intense abandonment issues and dreams about me cheating on him or leaving him almost every night - he's cheated before in relationships and has a deep fear that now that he's finally fallen in love for the first time I'm going to cheat on him as some kind of karma and that he'll deserve it.

I, on the other hand, struggle with his past and also his job - he's a personal trainer and a very good looking guy who gets attention wherever he goes. I guess I have some self esteem issues because even though he is always telling me how beautiful I am and how proud he is of me I can't help but feel sometimes like women are looking at us together and wondering why he's with me. Even some of my close friends have tried to have sex with him. It's very difficult for me for him to look the way he does and work closely and physically with female clients on their bodies. He's not vain and he doesn't seek attention from or flirt with other women, but he has told me before that female clients have signed up with him and then quit once they realised there wasn't going to be a sexual relationship involved.

It also bothers me that he has cheated in the past. He has told me that that was because he wasn't committed to those relationships and wasn't in love, which I believe - I don't think that he would cheat on me and it's unfair to judge him on his past but it's still difficult to handle sometimes.

I largely hide these feelings from him because I don't want him to think that I don't trust him - the problem is that it is very stressful for me to experience the level of jealousy and insecurity which I currently am dealing with. Sometimes it makes me want to quit the relationship which is so unfair when he hasn't done anything to make me worry and it's me not him. Does anyone have any advice on coping with these unwanted and unwarranted feelings?