Hi KUFF,
Welcome back!

Sorry to hear you are suffering from loneliness.
I understand isolation. I sometimes need alone time. However, it's nice to know we have friends/family when we are ready to socialize.
Your friends "turning their backs on you" seems especially sad.
Sometimes, if/when we chronically do not feel up to socializing, friends get frustrated and stop asking/inviting us. I cannot say those are the dynamics in your life, of course.
In the U.S., we have a network of "meet-up" groups where people with common interests meet up and share their time and interests together.
Some potential ideas: Workshops of interest (many are free), coffee houses where people meet up, gym memberships, adult classes/lessons, etc.
My family-of-origin has not been helpful. Sadly. I have come to acceptance on this.
Others in my life have been able to join in mutually supportive friendships.
I have met my friends through pursuing common interests via classes, workshops, trips, etc.
I also invite in neighbors for meals, send them meals if I hear they are ill, etc.
I hope you find some ways to meet more friends and gain support.
Again, Welcome Back!

WC