You're not 'friendzoned'. You're just friends. Sorry to be blunt about it but if he has a new girlfriend and it isn't you then he doesn't want you in that way.
You've been friends for 2 1/2 years which is probably why he's so willing to care for you in the way he does. As for 'half cheating' I disagree with the above, you can't really half cheat. He didn't want to have sexual contact with you when he gave you a massage and didn't display sexual interest during it according to you. You've shared a bed but that's it. Is that weird? Well, yes. If my partner was doing that I'd be pretty confused and maybe uncomfortable enough to ask that he didn't do it any more, but he hasn't actually done anything with you- maybe it seems like you have because you subconsciously think he wants you and not her.
It does sound like you're projecting more feelings onto him because he cared for you when you needed someone there. Sorry that you had to go through whatever it was you needed the support for, but may some time away from him to settle yourself properly would be a good plan.
I would advise that you leave him and his girlfriend alone and let them have their romantic relationship, and don't try to snatch that away from her by telling him you want to be friends with benefits (which would probably involve breaking up with his girlfriend.) He's his own person capable of his own decisions and if he didn't want to be with her, he wouldn't be. If he becomes single and you want to know if there's a possibility of there being something between you, ask him then.