ladies I need relationship advice !!

**PLEASE NO RUDE COMMENTS** so to start of with I'm 18 years old and my boyfriends 21 almost 22 . We have been dating for almost 2 years . so lately we have been fighting a lot and it's because he lies to much I have found out stuff and when I ask him he always finds something to lie about when in reality I know the truth and he gets all pissed saying that he's not lying and stuff like that . Like 3 months ago I asked him why he had unblocked his ex and he said "idk what your talking about " when in reality he knew what I was talking about and I sent him a screenshot and he said "idk babe maybe they unblocked them selfs " I was just like wtf r you fuking serious how is she just ganna unblock her self and the rest of the people aren't ??? Like really !! So this past days we have been fighting a lot because he lies about like little stuff which it bothers me and when I asked him he lies about it and today we were just so fine and when I check he had unblocked his ex and I told him "I'm tired of your shit really u did this again when u promise me you won't do stuff that you could avoid so we won't fight " and he said "what are you talking about "and I said nothing just forget it I'm just tired of your shit " and he said "tell me " and I told him "you unblocked your ex again from ig and I know what your respond is going to be already @" and his respond was "who cares she's just someone else to me already she's just another person to me who cares if I did " so since he couldn't lie no more cuz I knew the truth he just said that so my question here is how can I leave him like I love him so much I feel like me and him have mad love for each other every time we r going to fight we say "you know what we should leave this here " and if I tell him "well it's up to you what ever u want to do " he tells me "well idk what to do what do we do do we brake up or what " and I tell him "idk it's up to you if u wanna leave me " so we never end up braking up and the reason why I can't let go of him is because 8 months ago me and him had a baby I had him when I was 4 months pregnant almost 5 so I had a miscarriage so this is how I feel like i can't leave him because I really love him so much and I feel bad also leaving him because we once had a baby together and I just feel like I would make the baby sad if I were to break up with him so It seems like I can't never let go of him bcuz I feel like I love him to much and sometime I feel like he feels the same way he tells me that we should break up and stuff but we never end up braking up and when he wants to he makes it seem like he dosnt care if I leave him but the thing is why dosnt  he leave me if he really wants to break up with me ? Please no rude comments I just need some advice here I really love this guy but sometimes I just feel I can't with his shit no more and I feel like if I keep been here since I accept his lies he's ganna keep lying to me and maybe do worse shit since it looks like if I was accepting his lies when in reality I don't like that shit . Thank u in advance .