Hi.
You're in a very tricky situation and it really is quite difficult to determine why he's doing what he's doing. Honestly, when I got the chance years ago to flirt with my son's mom so I could get free sex, I would. It felt quite good being in control and the freely given sex wasn't so bad either. Fortunately for both of us though, we now find ourselves in our present situation -- we are together trying to raise our family of one 12-year old boy and two young girls.
How can you tell? There's no hard and fast way of doing this but you can try to invite him over to help you with the baby. Do this often and let him work like a dad and/or a husband should. Will he rather watch the tube or do the dishes? Will he take out the trash or mix formula? Will he leave diaper duties to you?
Oh, even if you really, really want to and your hormones seem to demand it, say no to sex. You know by now that sex muddled up your relationship before. It will again if you don't know how to say \"no\". See how he reacts when you constantly refuse. Please do not use your body to reel him in. That never works. All it does is to make you an easy lay. Sorry to be harsh.
Have a look at how he reacts when your baby is acting up. Try to invite him over when you know he'll be tired and see how he acts with all of you.
In my country's history, a suitor was once expected to render labor to a woman's family if he wanted to marry her. That was for one year and only then would the woman's family determine if he really should be given a chance. That practice is all but gone now but it sometimes seems to make sense especially with more and more guys (I seldom use the word \"men\") showing themselves to be nothing more than big mama's boys.
What we really need to find out here is if he really wants to be a father, husband or whatever and we need to know what that whatever is. You cannot allow yourself to be used in any way -- physically, emotionally, psychologically, etc.
If he starts showing that he wants to share this experience with you and be responsible, then it may be a good idea to give him a chance but let him earn his place in not only your life but your baby's life. All guys have a hard time being a father. I did. But as long as he shows the desire and, more importantly, the tenacity and faithfulness in this new role he seems to want to play, then he's allowed a few mistakes. Even the best of the best basketball platers started with fumbling the ball.
Give him the benefit of the doubt because you and your baby deserve a chance at a life together. The question you need to answer now though is whether you will be sharing a life together.
Don't fall prey to just wanting to have him back but don't be too scared to welcome him back if he deserves it.
Whatever you decide though, always base your decision on what's good for you and your baby.
Please take care of yourself and your baby and keep all of us here posted.
Erick