I was advised to post this in the relationships section, looking for some advice.

For the past 16 years my mother (divorced) has been having a secret life with a married man. 6 years ago I found out and this was taken as an opportunity for my mum to use my as her 'get out of jail card'. Before I knew what was happening I was lying, keeping secrets and doing as she asked. I tried to keep this man at a distance but he became so involved that now he is like a father figure. I am 22 and this has consumed me for too long. I feel so much guilt and betrayal. It follows me where ever I go because I keep lying for her and keeping the secret. Recently there have been signs that my family have known about it all these years. Suddenly I feel betrayed by them. I've been through so much anxiety and stress trying to hide it from them and feeling guilty for it. I don't know how to talk to people about it because I've been told not to for so many years. But I need some change in my life now, I need this not to consume me in stress and anxiety like it is. It is getting worse and I am going home for a month soon and I really don't know how I will cope. Any advice would be great.