boyfriend advice help

Okay heres the thing. Me and my boyfriend have been dating since highschool. Its been 7.5 years together. Me and him and alike we hang out with the same people and we love eachother a whole lot. Hes been out of a job for a long time. He is on and off with his job. I am a manager at a grocery store for 7 years and I make good money. I usually pay for him sometimes. Or his mom gives him money. Ok.. now… my boyfriend likes to flirt with girls online. He says nothin is going on but I know. I have caught him with fake sn’s before and confronted him and all he says is that he is bored and he likes jokin with girls online. Now in may of 2008. While I was at work he was talkin to this girl for a couple weeks. I didnt know anything. He wanted to meet her up and have sex or do stuff. I didnt know this. So he meets her up at the library and they have sex in the car in his CAR. I didnt know he told me 2 days after this happend. NOw my boyfriend is honest to me at all times. I was soo upset I cried I was depressed for 2 weeks. I didnt know wht to do. HE said he was mad at me and decided to cheat. I was sooo upset. I couldnt do anythin. He says he has no connection with her and never wanted to do that again he told me. I was like why did you do that to me. After all id one for u. ANd he cried tellin me he loves me and he WASNT thinking it was a mistake and he was mad at me. im like ya wutever. NOw previously he tries to meet up girls from online and he told me he went to go meet up this one girl but never showd for a blow job at teh park. and I know if he is lieing to me. nothin happend. I forgave him and im still with him. I never cheated on him or lied. IM a sweet girl and im honest. He says he loves me. BUt I know he still is flirtin with girls online and wantin to meet up he says he just gets bored and nothin will happen. Do you thnk he will do it again? im so scared.. I want to get married to him but I dunno… I love him… he has nno job. I pay for him.. and im scared… I dont want to be cheated on…he always accuses me and I dont do anythin. im always at work or im with him and with all our friends or im home from a long day of work… I need help and advice …I know this is long but this is serious…I do love him a lot. and we do everthin together. OUr sex life is great… idunno why he would do that tome. he tells me now he wont ever do it again… wht do you think??