OP, you’ve been given similar advice before and you seemed to take it on board and were thinking about developing your own interests and getting out and socialising more. You don’t even really need to do that, there’s nothing wrong with being an introvert or enjoying spending time at home and with family more than going out.
But it is wrong to insist that somebody else changes to fit in with that. And it’s not fair to resent your partner because he has more friends than you and a more active social life. You’ve said yourself your partner is perfectly happy to help with childcare if you want a night out or to go away.
Your partner has more friends than you and a more active social life and this is making you unhappy. So you basically have three choices.
You could decide that you are going to try and develop your own interests, social life and friendships. You could join groups, make an effort to socialise more with DPs friends and their partners, invite them around, have nights out. Make your own friends and have your own interests so you don’t resent DPs.
Or you could accept that you are an introvert and a homebody and enjoy being at home with DP and DD and recognise that you don’t feel the need for a big circle of friends or nights out all the time. But also recognise that your DP is not an introvert and be happy for him to see his friends regularly and socialise even if it’s not your thing.
The third thing you could do is carry on as you are making your DP feel bad and sitting at home full of resentment and bitterness when he’s out but when he’s at home have him feeling bitter at not being allowed out. And of course having his friends resent you too.
The difference is in the first two cases you will both be happy. But if you continue on like this you will both be miserable. And I agree with a PP who said the deletion could well be a sign DP is getting his ducks in a row to leave.