Why is my ex mean to me now?

well iam 22 yrs old i have a daughter n everything, im getting ready to have my exes child. he is 22 yrs old too., he was all mean to me at first .. like get abortion if u dont i will leave which he did, well we decided to be friends i guess. but it really doesnt feel like we are, 2 he came bout 2 weeks ago. acting all nice to me ,,, n to my daughter, n everything,, we fooled around but ,, after that day hes been mean to me, ingoring me,, n everything , i text him just to be nice, but hes like i have a life n other friends, i dont want to text all day, i was like ok, n he started to ingore me even more n be mean to me, he has his days wheres hes just mean, n sometimes so nice, he doesnt treat me like a friend really, cuz u dont turn on ur friends.its just after tht night, he refuses to answer me bac half the time.. i asked him if we were still friends he doesnt reply back i mean ive done everything to try to stay friends. i mean whts wrong with him now lol .