What would you do... because my head and heart are not on the same page

So I have been with my S/O going on 6 years may 1st we have 2 beautiful girls together and I'm 31 weeks pregnant with a boy. Right after our second daughter was born I had caught my husband messaging other girls for pictures. It put me at a all time low but I forgave him and things were going great. Well back in January I had caught him snap chatting a ex from way before our time. She was inviting him over and saying shed make it worth his while well he never went but he never said no just told her she was impatient, that's all I could see due to it was snap chat. Idk what made me curious to snoop that day but I'm glad I did. I left him but let him weasle his way into forgiveness but fast forwarding to present time. I cant stop wondering if he lies when he goes places. I wanted to delete social media and snap chat and he refused. It's gotten to the point I literally check his boxers when I'm doing laundry and honestly every time there is stuff in them so I just get more paranoid. My head tells me to be smart and to just start looking for places and jobs. My family all lives hours away and dont want me to move in with them they want us to work our issues out like old times but I just feel like you can't work things out with someone who is unfaithful yet says they love you. I'm a stay at home mom so have no money no place to go I'll be starting completely over and honestly I think that's why I stay because it's easy and kids adore their dad. But lately I've wanted a fresh start to either 1 have us change cities so I dont have to hear the rumors and see his ex he was chatting up or 2 go to my parents city and start job searching and apartment hunting. I've had so many people tell me I'm being rational but I had my first son at 17 with my high school sweet heart and as soon as I was 8 months pregnant he starting fooling around on me and I forgave over and over for 2 more years before I had enough and I told myself never again would I be that "dumb women" yet here i am and i feel like I'm her again.