She gave him two children, of cosure he has feelings for her. Now if they're romantic, loving and warm feelings as in he wants her back, or he just fixes things for her because the kids live there are two different things.If you truly do love this man, just talk to him about your deep-seated fears. You two have to be in a position of trusting each other with your emotions and your fears. If you don't then he's never going to get very serious with you.However, if you show him that you do trust him and need his reassurance, just let him know its not jealousy, just that you want to make sure its you he wants from now on, that's all. He can't fault you for that. You've invested four years with him. That's a long enough time to gauge where your relationship is going.Finally, I wouldn't push marriage too hard. He's been down that road. If he really loves you, and you two are secure enough in your relationship together, then give it time. There's no particular rush unless you're asking for that for religious purposes, for childrens' sake or some other reason. Love is love with or without a piece of paper between you.