Based on my reading of your letter, you are struggling with two main issues. One is that your stepfather sexually abused you and you are deciding on whether or not to tell your mother. The other issue is that you have cheated on your husband and are having difficulty knowing how to stop this behavior.
You said you feel like you are living a lie. I am assuming this is because your mom is still married to the man who sexually abused you and you have not told her. You also mentioned that you do not want to hurt your mother and that is why you are withholding this information from her.
Should you tell your mother? First, it’s helpful to examine why you want to tell her. Why now? Is it that you are now ready to tell her whereas before you might not have been? Has something happened as of late that makes you feel that now is a good time to reveal this to her? What do you hope will happen when you tell her? Do you want her to leave him? Press charges? Try to examine why you want to reveal this information to her.
What will she do when she hears this news? Be prepared for the possibility that she rejects this information. Know that she may not be “ready” to hear or accept this information.
Ultimately, the decision to tell or not tell is a difficult one. But please recognize that you were a victim in this situation. Your stepfather violated and hurt you in profound ways. Your life is forever altered because of what your stepfather has done to you. None of this is your fault and you have the right to make it known to your mother that you were a victim of his abuse. Your mother may not like what she hears but it is the truth.
As for cheating on your husband, you said that you felt that having sex made you feel like “a person.” Possibly because of the abuse you have endured, you may have come to believe that sex equates love. Having sex, in your mind means that you are loved and this belief may be the driving force behind your desire to cheat and have sex with others. But in reality sex has nothing to do with love and cheating on your husband will probably only lead to a divorce. You cannot continue your marriage this way. It’s not fair to your husband and it’s unhealthy for you.
Because the issues you are dealing with are so complex, I would strongly recommend seeing a therapist. You will need more guidance regarding these issues than I can provide in a short response to your question. It is particularly important that you work to correct your thinking regarding love, sex and marriage otherwise you may soon be facing a divorce. A therapist can help you work through all of these issues. Thanks for writing.