Doesn't matter if she's right. The point is she insulted me. Did she have to laugh and say I can't have a child? What was the point? Couldn't she have kept that opinion to herself? Did she expect me to not be insulted? Did she expect me to still want to hang out with her and to still have a good time with her? And who is she to judge who's a good parent, when she isn't with the father of her child anymore, when she was lying naked on my bed talking to her son on the phone, when she doesn't mind having sex with a random guy when she's abroad for a few weeks? And I don't think you are in a position of authority to judge me either.
You ask if she expected you to want to hang out with her and have a good time with her after she insulted you, but you did just that by letting her spend the night and having sex with her.
Who are you really mad at here? Her for insulting you, or yourself for thinking with your penis and letting her hang out, giving her sex, and then agreeing to a date after she insulted you?
People do what you let them do. And have you heard of the saying, drinking poison and waiting for the other person to die? Just move on and learn how not to act the next time someone insults you. Most of us have been in your position where we wish we could go back and stick it to the person who we let insult us but the key is not letting that happen again by calling them on it right there and then or just nexting them.