Boyfriends ex having his child

[S_BEAN]

So my boyfriends ex is having his son.

Some background info...we met at work while he was dating her. We had a connection and both of us fell for each other quickly. Hours on the phone, so natural to be together, great friendship that turned into a great relationship (shortly after he broke up with her because he just didn't feel love for her). He had been married before (divorced for 5 years) and had sworn up and down he never wanted to get married again. He knew marriage was something I wanted down the road with the right person and when he was pursuing relationship I told him I couldn't because marriage is something I want - not just a very long term relationship. He took some time to figure out if he could be open to that and he was. A few months later - I love you's were said by both of us (something we both take very seriously and don't just say it to say it) and he said he could see himself marrying me. All of that was said just to let you know how our relationship is.
The twist...his ex tells him she is pregnant with his child. The breakup was bad because she loved him and he just didn't even have serious feelings for her. She moved out of state for a job and very little contact was had between them while she was pregnant. I haven't been worried about them getting back together until now. Today is the due date and he flew out to her state for the birth of their son. I expressed my desire that if she for any reason shows feelings or broaches wanting to get back together he tell her it wasn't going to happen. He agreed but gets very easily frustrated when I make requests or ask a bunch of questions because he thinks I'm jealous and insecure - both of which he hates. I try to tell him I just need periodic reassurance from him because another woman having his child and sharing parenthood and all of those wonderful (and possibly bonding moments) with her is very, very difficult for me. I am trying to be supportive because he is so stressed at the moment because fatherhood is something he takes seriously (especially because his own father did not and he doesn't want to be like that towards his child). I am trying to think about how to handle this. My love for him is something I didn't even know was possible. I want him to stay in my life forever and I would love if we could eventually get to the point of marriage and having our own children. I and ok with his new son being around and I am ok with less attention towards me -  I completely get how that is necessary. I just really need advice on how to handle his ex being in his life permanently now. Thank you so much :)

[Lee_1989]

If he and his baby momma want to be together, let them. I don't think you want to be the one who stands in the way of a family being whole. You need to trust that whatever happens will be for the best (and if he chooses her, you're off the hook for being the "wicked" step mom ;)). And if it happens to be true that he prefers you over his baby momma, TRUST HIM when he tells you that, because he means it. I mean, think about it: if he wanted to be with her, they wouldn't have broken up. However, if he changes his mind in the future, he's allowed to do that. You two aren't married and you deserve someone who wants only you. I know it's tough when things seem to be up in the air and out of your control, but whatever is meant to be, will be. Don't try to force something if you both are miserable and fighting over jealousy.

[Londres70]

How long have you two been dating?

Is he certain this child is his?  He should make sure of that.  

Telling him how to handle the situation does come across as being jealous and controlling.  I am not saying you can't voice your concerns, but telling him to tell her "it wasn't going to happen" wasn't something you should of said to him.  Besides, that's not really an appropriate thing to say to a woman who just gave birth to your child......not the appropriate time to be saying something like that.

I agree with RR.  If this child is indeed his then this relationship isn't going to be the best for you in the long run.  You are already becoming unglued and she just had the baby.  

[RockRose]

Let him go to her.  This is his former partner,  and his baby.  

Let him go.  

Find a man who doesn't already have a partner and a baby.