What are the signs that an ex is on his way back to you?

You know, I think you've answered your own question here, and it's to do with you and not him. The fact that you have identified him as immature and an ex suggests to me that you are more than ready to move on, and to go back to him, even if he wanted you back for any other reason than he can't find another girlfriend to replace you, would be a waste of your time and his. So take charge here. Tell him it's over, to stop calling (use your caller ID; that's what it's for) that you have no feelings for him, and you are not going to be his sympathy date. Of course, if he's really immature, there is always the risk that this kind of firm treatment will make you that much more desirable to him, but he'll get over it eventually, unless you give in. Phil