It isn't what you have, or who you are, or where you are, or what you are doing that makes you happy or unhappy. It is what you think about.
When I see someone who is starved, they don't look alert. They don't have boundless energy. If you're too skinny, it looks like you're near death.
I get weary of reading about rebirths because we're all growing all the time and it diminishes the life you've lived if you say 'I'm a new person.'