Have you suspected that she could be involved with another man? Spending time in the bedroom alone, a lot of contact by blackberry, isolating herself from the family, and all those trips with supposedly "friends" looks very much like there could be an affair.
If you have access to her phone bill, emails, etc., you need to get information to see who she has been contacting. Keep all the information to yourself and do not reveal what you know or how you know under any circumstances.
Do not ask her if there is OM b/c she will deny it. If you confront her about contacts you've discovered, then she will say he's "just a friend". This is typical WAW script. So, don't let her know you are even suspicious right now.
If you discover there is OM she's contacting, then you can go over to the infidelity forum and get a play by play from Allen how to handle the stitch.
I'm sorry to say that she seems to be showing all the signs. Keep your cool and try to find out what's she's doing behind your back.
It is not about what you feel should work in your M. It is about doing the work that gets the right results. Do what works!
