I'm so sorry to hear about all of the bad news and I hope your Mother-In-Law is okay. The increasing frequency of friends passing started for us about five years ago, when we were in our mid/late forties. Going through that phase of life changes you and it definitely makes the urgency of living move much more to the forefront.
I just had an old high school friend pass last week. He had been battling cancer for about a year so it didn't come as a surprise. I hadn't spoken to him since we graduated. We were in marching band together and I remember those days so clearly.
These experiences of middle age really make you not want to take time as much for granted or put off reaching out to those friends and family that you've been meaning to catch up with.
Our time here really is so short and we don't have much say about that but, on the bright side, how we use the time we have left is mostly within our control. Hang in there!