Context, I am 17 years old and in a few months I will be 18, I don't know if the correct word to define myself would be introverted or another but oh well.
The fact is that I only have 4 friends with whom I feel comfortable, I have acquaintances to call it something but I don't connect much with them.
The one I would consider my best friend has invited me a few times to go out with a group of people my age, among this group there are people who belonged, to give it a name, "my old friends" who kicked me out through the back door of their group, although I have no resentment towards them, nor do I know if I would like to meet them.
I am also in an athletics club and although I don't have many friends I get along well with the boys there, there are also many girls, maybe too many, I literally think there are 4 boys and 15-18 girls and if I have a problem talking to the boys with the girls you wouldn't even imagine it.
What could I do to be more sociable?
Also lately I feel quite sad, not depression type but a lot of depression.