Hey Alexandrias
You need to have a proper chat with the fella really, it sounds like he has insecurity issues surrounding his own inexperience rather than anything you have done. He is either seeking reassurance that he is the best thing that has happened to you and you will never wonder about your old life, or he is wondering whether he is good enough compared to all your previous experiences.
Some areas you might want to discuss:
Does he really have a right to judge your past?
His inability to get beyond your past is his problem. You didn't do anything to him, so its his decision whether he can get beyond the past. But you need to tell him random ad hoc accusations cannot go on.
He needs to realise that you were not born the day you started dating him. No one has a totally clean slate.
He needs to accept you for who you are - both the good and the bad. Use that acceptance to create a bond that holds your relationship together.
If you or your partner allow your past to define either one of you, you are living up to a label, not your personal truth.
If you're being judged, tell your partner: "You can either trust me or not � but get off my back!"
Don't hang on to bad feelings from a past relationship or experience - as difficulkt as that may be - they will only infect your current relationship.
Define a new standard for the relationship. Commit to it together, and make a new plan for your life together.
Everything you do in a relationship either contributes to it or contaminates it. Ask him what is focusing on the past doing or achieving?
I wish you all the best, but it is something he needs to get over and deal with. If he can't do that through honest and frank discussion, then can you ever rest and relax, knowing that these thoughts are forever churning in his mind?