I think your analogy fits beautifully. I do think MLC is like a cancer. It poisons what was once healthy. Divorce as chemo fits as well - it's supposed to "heal" - and in ways it does. But it also changes many, many things. Your appetite, hair texture, sensitivity, tolerances, - you are you but different.
I too am very sorry for your brother. I have a friend whose husband has entered the tunnel and she is devastated. They have always had significant problems however she has 2 teenage boys who are watching their dad become an adolescent in front of their eyes. Hanging with college kids, partying til all hours, being foolish.
I look forward to a time when I can share my life with someone (married or not) and just enjoy the moments. Holding grandkids, reading, golfing, ...I'm really not looking for more - just looking forward to enjoying all I have!
Have a great day! You are amazing!
M-48/XH-48 M=25/T=28 years Ds-24,22/S-18 D - 3/11 A Day at a Time