Talk to me ladies :( my boyfriend cheating :(

I just had my baby 2 half weeks ago and my boyfriends is with another girl as I write this I’m heartbroken! I’ve called him and text him and he’s just ignored me! But my best friend seen them together so I know it’s not a lie and I’ve had my suspicions! I just need a bit of advice and someone to talk to right now as I seriously can’t stop crying! Im looking at my newborn thinking wdf have I done this we innocent baby stuck in the middle are our fked up relationship! My hearts in bits