sad very very very sad

so i live together with my baby girl 3 months old. me and her dad aren't in good terms so we decided to split up. he has his own apartment and i have my own which was ours but he moved out. i feel so depressed and sad it has gone this far and the way it is.. like my heart torn into pieces. he comes and sees her all the time and he takes her over to his house . im afraid he will find someone else and or letting girls into his apartment with OUR baby girl. i still love him so much but he doesn't anymore since we always argue . he never cheated never did anything just me and him weren't on good terms and never agreeed with each other.. i really want him back and to live with me but i don't think he wants to live with me at all anymore .. how do i tell him or what should i do if i want him back?💔 i don't want him to find another girl or else my heart would shattered and i'll go crazy . . i don't want anyone else but him