Only if she didn't like you... if you were good with her you'd become just as enmeshed with her and the family as Peter has become. Let's face it, they aren't just his parents they're roommates! Time to cut those (psycho) apron strings Peter! Stop banging easy girls from the club like your mom seems to want you to. Talk about hell, can you imagine waking up at Peter's mom's house when the booze wears off? It's like a bad college roommate moment: "No, don't worry, we're good. I put the ribbon on the door." I'm sure Babs loves coming by his closed door the day after he's been out partying and saying 'atta boy Peter, that's my boy!!"
Let's not forget there was that telling moment (beside the windmill) about Peter in H.B.'s season: condoms in the car. He's just a horndog not ready for a relationship let alone an engagement. 'Immature' barely covers the extent of it.