seeking advice

so things between me and so havent been so great lately an i feel alone i use to be able to turn to them and feel safe but recently ive lost my trust in them we have a 6 month old and i love them to peices they say that i havent been the best but alls i seem to do is put all my effort in an it hurts i caught them sending pictures to there ex and when i confronted them we ended up arguing and it all got turned on me i donno what to do if i walk away itll hurt me seeing them with someone else and with having a baby together theyll always be in my life but before we had our baby things were amazing they promised theyd stick by me an all the other false promises any advice.