I absolutely love my life!
To be honest, it's never been better - I'm in my 60s and have had hard times: divorce, single parent, severe financial worries. But those time are long gone and well behind me now.
My children have grown up and flown the nest so no worries about schooling/childcare, and my parents are no longer with us so no elderly care worries.
I look back and I'm pleased I used my life to do many things/different careers/travelled the world - much of it on a budget, I have never been wealthy at all. I cringe at the mistakes I made as a younger person but I also recognise that they were learning points in my life - I have learned to accept my past self, put right what I can and then move on as a wiser person.
These days I am truly content with what I have. I'm a pensioner on a state pension but can afford to live, I rent (but a beautiful place in the countryside which I love), I can afford to run my car (gives me such freedom to visit places and people, and enjoy the countryside), I have a few hours part-time work as part of a small friendly work team. I have loads of hobbies - writing, painting, photography, baking etc., and take part in lots of activities - church, evening classes, school governor and so on, so plenty of contact with others of all ages.
I'm older and less sprightly than I ever was but I do believe I'm at my happiest. I think it all depends on life stage and whether or not we are burdened with too many responsibilities, and whether the people around us are friendly and supportive or drain our energy (or worse).