Yes, watch her behaviour - but be careful your assumptions don't make her into an enemy when the facts might be simpler - she's unhappy and is trying to make herself happy.
This is absolute gold and stated so simply.
I completely understand her being unhappy, we actually have lost 4 family members in the last 2 years. Additionally, the kids are now self sufficient mostly and she sees that and feels unneeded at times. If fact she and the kids have been in more squabbles lately. Partly because she is trying to get them to do more around the house and they resist. The most recent funeral we attended for our brother-in-law (6/18) she seemed to be warming to me, we sat together at dinner and she seem almost wanting to reconcile by smiling and joking with me. Is that just me reading her wrong?