Relationship Insecurity

So to give a little back story: I was with my high school boyfriend since I was 14 until I was 20, so 6 years. I never thought to not trust him or think he'd ever do anything to hurt me. At the end of our relationship he let me know how for 4 of the 6 years he cheated constantly and the only way I found out was because he moved away for a job opportunity and got caught. It messed me up, it made me question my self worth and crushed my trust forever. Fast forward to my new relationship. This man is the best man I have ever met, he treats me like a queen and makes sure I have all I need. He has made his mistakes in the year we've been together, not physically cheating but emotionally involving nude pictures of exes but he since has cleaned up. With that being said I can't seem to get over my insecurity and my ability to trust. I love this man more than life itself and every part of me wants to trust him and show him I do but no matter what happens that side of me always shows. It's almost as if I can't even control it and I will just get upset. I am pretty insecure with my looks and I feel as if that plays a huge factor. I know I am just pushing him away whenever I get upset and I want so bad to move past it and stop but it's an endless cycle. Has anyone felt the same and been able to overcome it? It's ruining the best relationship I have ever had.