What do I do??

He keeps messaging another girl, someone who he works with, and every time I find out it breaks my heart and he begs me to stay and so I do. And we have an apartment together so I’ve never really felt that I had the option to leave and end things. But now I’ve found it again and this time it’s different because I’m pregnant, and I don’t want this life for me or my baby. I’m tired of my heart being broken.