I'm 17 years old and I've been with my boyfriend for a year and a half. He's 19 now, and we started dating when he was 17. He had me wrapped around his finger, and I was crazy in lust over him. He had a reputation of being a swinger, and everyone was telling me to not get attached, but I did. After a week of dating HE CHEATED ON ME. Surprisingly I wasn't that surprised. I broke up with him, and after a couple of days I was back with him. He was good with words, and I was a fool. He continuously cheated on me, and I would break up with him, and he would write me notes, and call me and tell me how much he needs me, and apologize and promise he wound do it anymore. He would lie to me ALL THE TIME In total he cheated on me 11 times(making out/touching), and he had sex with my best friend in my bed. We broke up. I eventually couldn't cope with the pain and started going out and looking for, as I called them "numbers", they would numb the pain of my broken heart. A month or two later, he came to me and told me that he's crazy about me and he can't live without me, and he needs me, I was pushing him away the whole time and told him this relationship doesn't work. He said it will work. AND I TOOK HIM BACK AGAIN(at this point it was 4 months of BS) When we got back together, he changed the way he was towards me. He started treating me good, and he doesn't talk to girls, or go out to parties. He made me his little princess, and we fell in love with each other. BUT I can't TRUST HIM. I'm paranoid when he doesn't pick up his phone, that he's hurting me and he's with another girl. And he doesn't understand that. When I see he is texting another girl, I break up with him. I'm scared every second that he's going to hurt me. And I don't know what to do. If I should just trust him, or end this whole relationship.

End the whole thing, once and for all. But something tells me you won't do that.

If you continue to so called love this cheater, and you do not even trust him. You deserve the treatment that you have got all this time and will continue to receive in the future. As long as you allow it to happen.

You can either just share him, maybe joint dates ( make it easier on him anyway)

Or you can respect yourself and dump him and find someone who will be true to you.

Yeah go out with him and the girls he is cheating with... same difference... maybe THEN you would get the picture.
You need to understand you are wasting your time.
IN HIS case ONCE a cheater/swinger ALWAYS a cheater/swinger.
You are letting his words walk all over you.
He doesn't care he can have his cake and eat it too cause he knows he has you wrapped around his finger.

You know that thing where kids put their fingers in their ears and scream "LALALALALALALLALALALALA"?
That is what you need to do when he tries to sweet talk you back... and I have NEVER encouraged that before

The major and only point here is that she has let him do this.

Yeah she has let him do this but she needs to realize that she HAS to correct it by dumping him. You can't change the past but you can correct it 'from here on out'
She needs the determination and conviction that she IS wasting her time and life on him

You will be kicked in your arse by him until you get enough, and dump him. Only then can you heal, and be healthy. My gosh girl, 11 times he cheated? And you took him back? You really do need some professional help. This is not love, its mental illness, by both partners.