i don’t know what to do

i am 20 and just had my first kid with my husband of two years. in the past, he had cheated on me and had a really bad problem with p*rn. a year later, we’re doing really good. he hasn’t cheated since then, bc I was dumb and gave him another chance. he promised me he’d quit watching that stuff. it was a boundary I had set early on in our relationship that I take very seriously. in my eyes, it’s like receiving n*sea from someone and pleasuring yourself to it. i feel like that is cheating. regardless, it was a boundary he agreed that he would stop crossing. i got pregnant a couple of months after bc everything was going really well. we moved to Florida where we could be with his mom so we could have the extra help with our newborn. i walked into the bathroom tonight to ask for help with our son, to find him m*sterbating to p*rn. i have been struggling with severe ppd and I am seriously heartbroken. I am a sahm until my son is old enough to go to school and left my state where all of my family is to make a life for us and our child. i am at a loss for what to do. i need the help and don’t think I can move all of my stuff and a baby again and I don’t have the means to do so. should i stay here and accept the help and try to just get over the fact that he watches p*rn and work in partnership with him, or should I leave and take my child away from his grandma who loves him so much and his father. please, any advice