Jealousy is a disease that drives men crazy, Your boyfriend's jealousy is not based on anything that you've done but his own insecurity and low self-esteem.
Who knows! Someone could have cheated and lied in his past but that has nothing whatever to do with you and he needs to know this! When he accuses you, be sympathetic and tell him that you know he's jealous but tell him also that all good relationships are based on trust and that you hope he learns to trust you soon because you are absolutely honest.
Tell him you will help him to get over this illness he has and that you hope that just by being together, he will learn to feel safe and secure with you. Treat this as his issue. Do not take it personally and let him know that.
Hopefully, he will be able to recover, with your love, from whatever has made him feel so insecure that he doubts someone who obviously cares so much for him!
Thanks
