The next whammy will be the empty nest situation. Have you considered going back to work, even part time. It will be very unhealthy for you to sit around all day worrying and wondering what your children are doing.
You've done your job and sound like a wonderful mom, although, a wee too enmeshed in your boys lives, might be time for you to reinvent yourself once again! Nothing in life remains constant, it either gets better or worse.
Sending hugs your way!