First, I want to commend you for not giving up on yourself and opting for suicide, that shows how strong you are and that you wouldn't allow your present condition make you stop living life.
Although you said that you are existing like a zombie, I want to let you know that it is possible for you to live a beautiful life if only you can re - enlighten yourself and try to look at the positive things of life
Granted you are getting to 40 years with no family of yours due to the failed relationships, dear friend that shouldn't make you give up on love. Just know that if you love love, love will find you again. Give it another try.
I may not know if you usually spend time around nature - maybe taking a walk in the garden or just be anywhere that speaks of nature? But just know that there's always this peace and tranquility that is found in it. I'm sure if you try it, you will find out more