pregnant and unsure of my relationship

so I am completely unsure if my relationship is okay right now I barely got into his phone and seen that he has been on Snapchat and meet me like if he wants to talk to other women or something and I know he already has but he says they are just old friends and I don't believe it he also get very mad when I look thru his phone or even talk to him about what he is doing it's like I can't say anything to him should this be a sign ? should I be worried? should I leave him I have honestly thought about it but everytime I try he always says something about me going back to my old ways or that he's gonna take our baby from me.. and that what is my daughter gonna think I'm trying to trust him but I just really can't anymore I love him I really do but I don't wanna look stupid or be getting played like I'm stupid. please help this pregnant woman who is just on the verge of letting it all down the drain not to mention our sex has not been so great lately and it's like he's not attracted to me anymore