Our grandparents didn't have this problem. Once their children had left home, and Grandad was retired, they basically took to their armchairs by the fire. Most of them never felt the need to have hobbies.
On the whole, our generation is much healthier and more active, and I'm grateful for that. Now that I've had my hip replaced I'm busy taking off the weight that crept on through inactivity. I've enrolled in an exercise class, aqua aerobics, and have signed up with the local gym. I'm also walking more, and take part in a games and indoor kurling group with U3A. All this activity means that I have less time for housework - which is a bonus!
I've always sung in choirs, for many years, and I think that contributes to my mental and physical health, and occupies at least two evenings a week. Have you considered joining a Community Choir, Bridgeit? Don't say that you have a terrible voice, because everyone says that - and most people have a perfectly adequate one. Singing together is enormous fun.
I hope that you find something that takes your fancy, Bridgeit, but I'm a great believer in curling up with a good book, some knitting, or the tv as well. We all need to relax. Your cream bun sounds very tempting, but I will resist the temptation until I reach my target weight, then maybe have one to celebrate!
Good luck in your search!