Being cheated on

Iv been cheated on before and it's really messed me up. I get jealous, over protected and I over thinks all the time. I have a low self esteem and it made me feel even worse about myself. Now I'm in a new relationship and my boyfriend has just turn 18 and will be going out in town for the first time this weekend. My anxiety is sky high because I think he's gunna cheat on me while he's drunk. Is there anything I could do to help my anxiety?