Exactly! The purpose of dating is to see how a relationship might work with someone. If there is no hope for the future - then let go and move on. This is just wrong on so many levels.
One of the best decisions I ever made when my marriage broke up was to never move a guy into my house while I was raising my daughter. Never to let her think it was ok to have casual sex with some guy I was dating. I believed it totally sent her the wrong message.
Yes, when Josh came along it made things a bit more challenging. When she was finally old enough - we talked about it and she was fine with him spending the weekend after he and I had been dating a couple of years and she was legal age herself.
And as for the "having more kids" thing. I asked my boyfriend about it in the early days. As I did not plan to have any more but he might want some. He was good with it but being honest was important. If he did not want kids - I would have ended it then.
I think you need to date women who are morally more responsible. I can't imagine my 18 year old fending for himself, my 16 year old living at Grandma's and my little guy attaching to all his new "uncles". This is just NOT a healthy situation.