Okay here's another one and this does not describe all of my potential dating partners, but a big amount of them.
People who have kids and declare that the kids are their whole lives; people who do not have kids, but talk about their dog like it's their baby.
It's wonderful to love your kids, and it's wonderful to bond with your dog, but to define your entire being around those is so unhealthy.
Many parents whose kids are already in university, and don't want much to do with them can often not let go. Often will spend their entire weekend fretting about their daughter or son who doesn't even want to talk to them and won't reply to their messages. Get on with life, lady. Get one actually.
And I love dogs, and I've tried to set aside and compromise on the "my dog is my baby" mentality, but it always comes down to that person being so completely disconnected from their own emotional core, you can never actually know them.