“My fiance has dick pics on his phone”

My fiance keeps going on dating sites. He knows I don’t like Snapchat (because he’s used it to online cheat before). ┬áBut I found it downloaded onto his phone again. So I snooped. I’ve found dick pics, pictures of girls, and online dating sites.

We’ve been dating for 4 years and live together. We made a family with all our animals. Our whole lives are financially and physically mashed together. I have no idea what do. Any advice for my sorry ass of a life?