He gave me an STD but I️ took him back.. not sure if it’s worth it

If you had a wonderful relationship with your fiancées 3 year old daughter - since the age of 1 -(& she calls you mom), how would you handle that if you two end up breaking up?

He gave me an STD and we have a 7 month old daughter between us both. After she was born (5.5 months later) I️ was in the hospital with a huge mass on my left ovary, the size of an orange. Interesting enough, we never had sex while I️ was pregnant bc he thought it was weird... (I️ am 28 & he is 31?).

We’ve had issues of him messing around before, hoped we were past that. Now I️ even gave him a chance to prove himself again - he has been doing much better but now I’m having pains again & the negative emotions are coming back.

Notsure what to do