YOU can't get her to WANT to work on the marriage. Only she can do that on her own. You can only do your best to be the best husband you can be and hopefully she'll find that's enough for her. This doesn't mean she'll always be happy, or want to stay with you forever, but at least you will know you are doing your best for everyone and especially your own child (and also giving this new child some stability).
There is never any guarentees on anything. You can just do your best (which is what you've been doing all along). My only advice is go slow, so you can both have time to heal, and gradually build a much stronger relationship.
It sounds like you have a good chance. And a safe place to start is friendship.
There is no arriving, ever. It is all a continual becoming.
