How can I forgive myself and others?

I am permanent resident in US. Got married 2 1/2 years ago, unfortunately my husband passed away. He's a truck driver and always away from home most of the time. I already knew it would be lonely here inthe US being away from family and friends before I married him but I never thought it would be so hard like this. I am not making an excuse but I think that's one of the major factors why I cheated on him. I feel so guilty especially when he passed away, I wish I could've confessed and asked for his forgiveness but it happened so fast, I never got a chance to talk to him..Even if he passed away, I know this sounds harsh but I still continued my relationship with my lover, he's only 16. He's minor and when his parents found out about our relationship, they forced me to signed all my titles (cars, house, everything) in return that they will not press charges on me. I am very scared and confused that time. I dont know what to do so I left the US and fly back to my country. It was a stupid mistake, that I took the risk to give up everything that I have to be with a teenager. I have a 5 y/o son and I sacrifice that bright future that awaits him in the US. I did this to myself, it was my fault. I don't know how can I move on from this.. How can I forgive myself and how can I forgive these people that took advantage of me because of my mistake? I don't know if I'm going back and fight for my rights or shall I just let it go and move on and stay for good here in my country?