Should i be worried if my bf added his ex on fb?

[proudhealth365]

okay we have been together for 3 years and before me he went out with ths girl for a month,she was actually known as a sl*ut in our school cause she went from boy to boy and she cheated on many guys incuding my bf. anyways i was on my bfs fb yesterday and a notfication popped up saying so and so has accepted ur friend request. and so i txted him asking why he would go add her and he was like how she was on his mini feed so he added her. hes like do u want me to delete her? but me being really insecure blew up on him and said a lot of rude things. at first he was like i did such a small thing why r u punishing me for and i still went on with my rude comments. anyways there came a point where he got mad back but i still didnt stop. once he stopped txted i calmed down and i tried to apologze but he was ignoring me and when i called him he shut his phone off on me.. i sent him multipe text messages saying im sorry .what should i do? did i *** up? why would he add his ex on fb? i cnt stop crying. im hurt tht he added her and now he wont even talk to me. i called so many times to fix things and i sent him many texts saying that im sorry and tht i shouldnt have spazzed. but im still angry that he added her.. how can i cope with this please help