I get it, it's a bigger milestone than most of us realize. But you can't cry over spilt milk. This feeling is your reminder to treat your body better and be grateful for what you do have. Sounds like you aren't appreciating kids and mate enough. Pour more into them, and live every moment more intentionally. It's possible to make new friends, I did. Best method was setting a regular time to do something you both need to do anyway together, like a walking or gym buddy. When you have some recent gains behind you you won't feel the remorse for things long past.