Is my 3 1/2 year relationship over? guys and girls please help?

My bf and I have been together for 3 1/2 years. We have always had problems with our sex life since 3 months of dating. he wanted to move in together, and get married. All he ever says is I just anna make you happy. Even though the sex life has sucked, he really did try to do every other thing to make me happy. He was the guy who all my friends and guy friens thought was perfect or was a good guy for me. Though, recently things have changed. He used to call all the time whle a work, and would get iffy if i didnt call him as soon as i got home from work. When i call him he say let me hit you back...almost like im a stranger. He used to want to walk side by side (im a fast walker and that uised to be a problem) Now he gets out of the car and is in the rstaraunt or store 5 minutes before I unbuckle. he looks at every girl that walks by, not just once or as a glance, but blatantly noticeable and then denies it and im standing right there. At the pool he used to be right next to me and would always play around or try to e right next to me. Now he has to swim alone and makes excuses for me not to touch him and swim away. He has to check out the other girls, m not being paranoid because ive never seen this before. in public he is stand offish. my gut is telling me its over, but when i told him things have changed. he has nothing to say except...I just love you and want you to be happy. in the past this has made me think thats truly what he wanted, but this time...i dont believe him. i think he is comfortable with me being around. then he alwasy cracks jokes about going ot the strip club, atleast 4 or 5 times a week! he says it to everybody. We were on a family vacation and he said it to his sisters husband in front of everyone. My heart is telling me this is over. Like right now i cant be in the same bed because my mind is just stuck on this. When i told him about his behavor change he said he will fix it. now i feel like its phony. Not genuine like it used to be. our lease is up for renewal at the end of this month and im thinking about asking him to leave. I just cant take another heart break like this. oh and i was using ecel on the computer one day and i leave my clipboard open for copy and paste, and i saw an email address for a girl named erica. i googled i and she was on blackplanet or something and apparently a stripper as stated on her page. i asked him about it and he denied it. he has several email accounts, soem not in his name. No one was at our house on the day it popped up! he denied it...but we have had problems like this in the past. Is my relationship over...what do you think