That simply is not true. Simply becoming heterosexual would not change the fact that you are single, have few friends, and struggle with lonliness and self-esteem. Plenty of straight people have those exact problems. You are focusing all of your self-hatred on your sexuality-- but, if your sexuality changed, you would simply focus it on something else. If you want to have deeper connections with other people, you need to work on self-esteem and communication skills. That would help you a lot more than changing your sexual orientation.

If you have not enjoyed being part of the organized gay community, then don't look there for friends or potential partners. Go to places you do enjoy. Participate in hobbies. Meet people at the places you like to go to. Friends are not going to care what your sexual orientation is. With respect to a partner (if you want one), it's a lot easier (at least in my experience) to meet people outside of the "bar scene" or the LGBT community center. I've never particularly enjoyed those venues myself. I've usually met people through friends (even straight friends), through hobby groups, or through online dating (where I list what my interests are).