Wow, I guess then that asking you to baby sit is out? Sorry had to get that one off my chest. Your feelings are your feelings your not wrong, your just diffrent. Quite diffrent for the most part. Get help if you feel you need to other wise just go on with your life. Many of your friends will or may already have children they will want to show them off to you. If you value your frindship I suggest you learn to lie a bit. Or drop the friend as soon as they have a baby on the way.
Good luck