My son wants me attend his wedding but I don't want to because I haven't overcome my problem. What Should i do?

I'm From Mexico but now I live in San Diego, California since 10 years ago. I work in a Grocery store. And I live with a friend. I'm 43 years old. My life has been a chaos. When I was 13 old I was a girl very promiscuous So I used to have with my boyfriend. I didn't take care about the risk having with out protection so I got pregnant. He was an adult but he didn't want to take the responsibility and ran away. My parents were very upset. I suggested abort the child but they told me that they would take care of me and my child until I got the adulthood. They were very tough with me but I think that I deserved that treatment. My parents pay me School and food and they brought my child up. First I hated that child but my mother taught me to love him. To me was very difficult because I wanted be free and have a relationship because my parents never allowed to have one and when I had the chance they met guys who just wanted . I felt that everything was fault of y parents trying to control my life. Even my parents got very attached to my son, I felt that they were guilty of my disgraces so When I became adult and I had enough money I took him off from them to live together. It was just a whim because I felt not ready to take care of him. I asked help to a friend of me and I tried to have my own life as my friend took care of my son. Sometimes my mother visited his grandson but i tried to don't let her stay for too much time. My love life wasn't change. Everyone just wanted and always betrayed me and make feel bad. I don't know what happened because he started to have a Strange behavior. Sometimes let him with that girl was a mistake. I started to live alone with him when he was 10 years old. Many times he made me get upset because I couldn't take care of him. He became a pervert and he used to spy me. Sometimes I take boys to home and I discovered spying. It really made me be scared. I punished him. Sometimes I wished called to my mother for help but my arrogance could more than my desperation. Suddenly that boy started showing me a twisted behavior. He told me that he was I'm love of me. He always told me that he saw as an Strange in his family but since he was living he loved me but not as his mother but as another woman. It was shocking to me. I almost got crazy. My love life was a mess and this kid was telling me that he loved me as a man not as my son. I was desperate and I tried to accept that I was a bad people and I was a useless woman and I couldn't be better mother than mine. So I tried to be tough but I couldn't it. He always was disrespectful to me. I called to my friend to take care of him and I tried to be away of him. I tried to hang with someone out but always was the same. He was a 14 years old and I was a 27 years old woman. He used to be naked when we were alone. My thought were turning twisted so I tried to accept that I wasn't a good mother so I sent my son with my mother for one year. I never said the true why did this Just i said It was difficult to be a mother. I thought was enough to him but i was wrong. He was the same. And my love life was the same. I punished him but It wasn't enough. When I became 28 I felt that my life was useless. He come to me and insisted in have with me. I really was desperate so I accepted. I made him promised me that he wouldn�t ask me again do that. But after that he insisted more times. He treated me about tell everything we had done to my mom. i was scared so accepted do it. It wasn't just one time. I don't know why but by first time I felt that he was the first guy who sincerely loved me. One part of felt guilty but the other felt happy. We had our secret: We were lovers. For 4 years I thought that my life was good but once time, when he was 21 years old I discovered that he has a girlfriend. i felt betrayed again. I asked him take her away from our lives but he didn't. I understood that I was wrong. I took enough money, left my life behind and I cross the border. After i got a job I communicated with my family. My mother was upset because I never said anyone that I would travel. For the 3 first years my son asked me get back he promised he would let his girl. One part of me wanted believe on him but the other know that what happened was just his lack of mother on me and the hormones. In my case was different because l love him yet as a man. No man has made me felt woman as him. I had many relationships here but no one has could change my feelings to my son. That's the reason because I'm alone. I use to go out with guys but I always say them that I don't interested on anyone. Many of them had tried to teach me english but I'm a bad learner. My son has changed and he reinforce his relationship with that girl and now are going to get marry. I'm invited to the celebration but I'm not ready. I have visited Mexico many times but I avoid to go to see m