Dear Dr. Love,I have been with my girlfriend for almost a year now. She has made many mistakes in the past. I thought her lifestyle of smoking and drinking was very bad and asked her to change for me. She willingly said she would.I had also asked her to stay away from one guy in particular becuase he really liked her and hit on her all the time, she also said she would. Not alone, i have also agreed to change some aspects of my life for her and to stay away from just about every other girl except for her.About five months later, i find out from one of my close friends that my girlfriend was in fact smoking and has been. This means she lied right to my face numerous times when i asked her because i was suspicious. when i asked her about it she lied and lied until i just caught her with everything and she slowly admitted the truth.If that wasn’t enough, then i asked her about a particular night when she was with her friend, and her friend’s brother and the individual guy i asked her to stay away from. She told me they were there for a minute. Come to find out they were there for hours and she went to the guy’s house alone with him for a short period of time to get a camera. i also found out she had been smoking with him behined my back for about five months and hugging him even though she forbid me to hug anyone that wasn’t her. and after i found out most of the truth.its been about three months now since then and she recently told me that she also danced in her bathing suit top for him with her friend. She says it was innocent dancing. . How am i ever supposed to first of all just believe she didn’t cheat on me and second believe her ever again?