FB can mess you up! Just like now, you are asking yourself questions as to why your BIL waited till now to add you as a friend.
Couples who are having problems will watch each other and use FB of relatives & friends to try to keep track of activities. The best thing is to leave that stuff alone. You have enough to deal with without wondering about the intentions of W's relatives.
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!
