Young at Heart

I have a colleague who is 76 years old and still practicing medicine. She is very active for her age. She goes to Aspen in the winter, to ski. She goes skydiving. This week she announced that she is engaged. Her fiance is 83 years old. They will have a commuter marriage since they reside in different states. I am very happy for her, but I cannot understand why she has the need to be married at this point in her life. (I hope she isn't pregnant :)