HELP!!! How do you go on after betrayal?

I'm in a failing marriage and just trying to look forward to the future. I don't want to be single I love being in a relationship but I'm scared if I will be able to let someone in after being hurt like this. Could people who've been in this situation please let me know how you entered your new relationship? How did it start, were u apprehensive or did they show u right up front they were DIFFERENT? I'm just so scared, pls only respond if you've gotten out of a marriage and have moved on and it doesn't have to be a serious new relationship it can be the be casual too, I need solid advice. Thx.