She kicked you out the bedroom 11 years ago, but you have two children of 8 and 6.
Are these yours or from other men?
Do you work or not? Does she work (job)?
It is hard for us to advise as we don't know all the circumstance, but I should imagine (if you are at work) then if she has to look after 4 children that can be very tiring so she may want time on her own so talks to friends on the mobile & facebook etc.
You say she is on Facebook day and night so who looks after the kids - feeds them, washes their clothes, ironing, gets them ready for school etc? Do you do it all?
Do they really go to bed at 11pm on school days? That seems very late to me.
If they do go to bed that late maybe your wife thinks she never gets any time to herself (or with you). Try getting the kids to bed earlier so that you and her can have time on your own.
Sadly having children puts a great strain on any marriage, and you have 4, which is a lot of work
Do you ever do anything together?
Do you ever go out as a couple without the kids?
But if I am going to be blunt, maybe she just does not want to be married to you any more. That can happen in any marriage.