How can I make myself trust again?

My girlfriend of a year cheated on me with her ex boyfriend. We were both going through bad times when it happened, I had lost a close friends to suicide and she has been suffering with her mental health for years (she has since been diagnosed with bipolar disorder). At the time I said I would forgive her and things went back to normal for a while, then she met with an old college friend and he started to tell her he loved her, she told him she was not interested like that but he manipulated her so she would be with him all the time by threatening suicide. Long story short we broke up for a while, three months..we didn't speak at all during this time and it was so hard we crossed paths at work again and we spoke, all the old feelings came back and after lots of talking we got back together. It has been four months since we got back together and I get jealous so easily now, I feel sick if she is texting people and convinced she will do it again. I have never in my life been jealous or had trust issues before. She says she knows its her fault and would do anything to change it but she cant, but she says I have to learn to trust her again as she loves me and wants our relationship to work...how do I do this?

We were together at the time she slept with her ex, we broke up a few months later. I do want my future with her I have never felt this way about anybody before. I guess its just gonna take time

I think you are stuck ...... I think you should move on from this relationship ....... She has broken your trust...... you have to get out of this relationship..... Find someone that you can enjoy and not have this hassle ......

Don't you think with time I can learn to trust her again? I have forgiven her its just about forgetting..surely if we both try it can work? I love her so much and don't want to throw it away

Anything is possible..... It is up to you, if you decide to stay then that is up to you. I just think it is self destructive for you..... Four months later and you are still feeling jealousy I would not blame you.... what you are feeling is normal..... she betrayed you, when YOU were dealing with a loss of a friend ....... I would have nothing to do withe her....... good luck with what you decide

I had the same problem! I had a boyfriend whom I loved SO much and he lied to me. It was way worse to be in that situation, but you and your girlfriend broke up. You weren't together. He did threaten her and she kind of thought what she was doing is correct, you can't blame her. Put yourself in her shoes. Your past is depressing, but if you let something like your past which can not be changed affect you now, the present, you will regret it even more when the present becomes the past.

The past has created this cut feeling in the present ...... I just think there is deal breakers in a relationship and cheating is one......

We were together when she cheated on me as I said before, I am not whining I am trying to get advice from people on things I can do to help my relationship move forward. I thought that's what this forum was for...clearly I have come to the wrong place. Thanks for all the input guys.