Think of how your missus would feel, she is pregnant with what i assume is your kid? Im sure you have had a million great times with her, and you've had the conversation about the future with a kid/kids and all the things you will do as a family etc etc?

Being the dick and fucking off now would be the most selfish, bastard thing to do, a kid will be born and you will have left your missus to bring it up herself or with another man who aint its father.

Stick it out, ignore the burd from work, have the kid with your current missus and watch how much the little one will being you all together, you will wonder why the fuck you were thinking about anyone else.

Appologies for the seriousness