Obsession over this guy is affecting me so much, i need advice!

so i dated this guy for 4 months, he has 2 kids and im k wit it, it was all so good at the beginning then he strted changing n i felt it to make long story short i broke up wit him and whn i did he tried workin things out wit his bby momma... even tho i luv him or at least i think i do i broke up wit him to see if he would try toget me bak, so i made a fake facebook added his bby momma and i saw all her posts and they had been together and he denied all this so things didnt wrk for thm, and he would call me but i wouldnt pik up or txt bak but eventually strted talking again till know but he says hes not ready for a relationship yet he acts like we are and i want him to be my bf but idk its complicated the point is i already caught him lyin so many times and i dont trust him at all but i luv him i think, or im so used to it u have become this obsessive person and its killin me i dont tlk to my friends a much i have stopped doin evrythin for him and ive done so many things for him sumtimes i think hes using me we would fall asleep on the phone evrynite and know lately he fall aslep" nn dont call me n my mind strts thinking bad things i feel like im the only one trying i cry evry nite practically im jus so use to him, i have become this obsessive person i hate!!! this was not me before its like i cant live without him its jus so much idk wht to do! i jus need advise