Many times our fear(s) can get the best of us. A lot of times it will cause more problems than just the one, which triggered the fear. As many times you begin to get upset about every little thing. Pretty soon you are fighting more than not. I pray that you do not let this happen. Is it possible that you tell him that you don't want to fight about it, but at the same time you want to settle the fact that you don't want this happening again? Then ask him to set a time to talk about it (within a reasonable amount of time). Then after you have set the time, you must not bring it up! After you have talked about it (and hopefully settled it) you must not keep bringing it up, or this will just push him farther away from you!!! If he will not agree to set up a time to talk about it, you may have to lay low, and not talk to him until he's ready to. During this time it is important for you to have an outlet to express your fears. So find someone that you can trust, or just come hear, and vent your fears, and frustrations!!!
Just remember he came back to you. It does not make sense for him to come back, and not want to work it out with you! If something does not make since, then it probably is not true!!! Keep telling yourself this, everytime this little fear pops up! Also, remember that you are not going to be able to force him to do something, or not do it, if he wants to! My Grandmother used to tell me that you will always get more with honey, then venigar! Whenever you have fear come on this prayer site to ask for prayer support, and make your fears known. This will help you to get it off your chest, and possibly help you to keep your frustrations to a minimum. It will also keep you from unnecessarily grinding on Alex. I'm not saying that you don't have a right to, but keep in mind that he cannnot handle it. Also, you can be right about something, and no matter how right you are, you can still loose! Just think about what I have suggested, and only do it if you feel it will help. I only know a little about you guys, and you know the whole story!

***Heavenly Father we thank you that Alex has came home! I pray that you guide his wife in their marriage. Let her begin to see clearly what she should do. Give her an ample amount of patience to do what she needs to do! I pray that Alex begans to soften his heart towards his wife, as she backs off. Begin to deal with him, and help him to see what this has done to his wife. I pray that nothing is happening between this other person, and Alex. I pray this in the name of Jesus, Amen!!!