First off Welcome to PC!! There's a lot of support & info here. Cruz the forums & post when you feel comfortable.

You have spoken of depression when no project is happening or getting involved but never feeling fulfilled.

Depression manifest itself in many ways & for many reasons. We aren't professionals but in your post you don't mention seeing a therapist or have tried any medications. Seeking this kind of help might benefit your ability to sort this out.

I do admire you for all the wonderful things you've done to help others. It is something to be proud of. Hopefully you can learn to appreciate & be content within yourself.

Best wishes, so glad you are here.