{{{SophiaM}}}
I'm sorry you're feeling this way. I've been there, many times and it's okay.
Honey, sounds like you're suffering from depression and you may want to seek professional help. Don't worry, there's nothing wrong with seeking professional help. Maybe they can advice you on getting on some anti-depressant just to help you a bit.
I tell my friends and families this advice:
"It's okay to be lonely, what matters is what you do with your loneliness"
We'd all been there. I still feel like I don't belong to "a" particular group. At my age, 41, my colleagues are much older than me. Most are in their 50s. But when I try to hang out with my age group, we don't seem to have the same intellect or interests. I have very few, select friends that shares my values & interests. Unfortunately, as we get older, they seem to slip by unnoticed and friends are hard to come by. Like tonight, two of my friends and I just went for a quick bite to eat and had some wine. I like that spontaneity and we share interests in wine.
What you may need to do other than seek professional help is sit down with yourself and try to discover what you truly like. One friend of mine discovered she liked painting and whenever she wants to get away from it all, she takes off with her brushes, her canvases, her paint and a chair and find a quiet place to paint the scenery. I discovered I like dancing and I got into salsa dancing. Another friend of mine discovered she liked to knit and she'd knitted all of us including our beloved dogs and cats sweaters and blankets.

Our pets hate it though.

You see the point I'm getting at? Get to know yourself. Take good care of yourself. Treat yourself as if you're dating yourself. Give yourself the time and attention it needs. Give yourself the rest it needs. I know some of this may sound obtuse, but some people just doesn't know how to "sit" with themselves. The more you pay attention to yourself, the more you will come out of this. And another thing that always makes me feel good.... give. Volunteer to a cause you believe in once you get yourself out of this situation. I love giving my time and money to the homeless shelters and food bank. It's one of my passion throughout the year. You'll soon discover that we're not in such a bad place after all.
But don't neglect yourself anymore. Go seek professional help.