Oh Berbel! Please do not think you are a failure, you are just about to start living your life for you!
Four years ago today, I was in your position. Married for 33 years, living and working abroad, but oh so incredibly unhappy. It had taken me a long time to build up the courage to leave, and it wasn't an easy decision, but I walked away from everything and flew back to the UK with just a suitcase. I had nothing and very little money (well none really) but my son put me up and after 3 months i'd got myself a little flat and bit by bit i've rebuilt my life, and the best bit of all is i'm happy, living my life for me.
If you really are not happy with your situation, be brave, and take that first big step towards a new life for yourself, GO FOR IT! ☺xx