cheating SO at almost 6 months pregnant

Celeste • First time mommy 👶🏽
I feel so lost. The woman he's been cheating with found my Instagram and sent me everything of videos/texts/snap videos that have been going on with him for 6 months, so the whole time I've been pregnant he's been cheating with this other woman, I keep going over the messages... and comparing what we were doing on each individual day. It breaks my heart that he could do this to us. I want nothing to do with him. I am so mentally drained. I feel so alone. 😞