As others have said, find a professional. It can take alot of tries before you find the right person, but it’s extremely helpful when you find the right person.

As someone with ADHD I also get anxiety with changes in my day-to-day events. My coping mechanism for a while has been coming up with practical contingency plans. That makes it so I at least have an idea of what to do and at what point there is nothing left to do. It’s helped me get through many situations.

As for your future and social problems, those likely need some personal analysis and personal change (professionals are meant to help with this). A lack of future is often not an actual lack, it’s usually a personal failure at seeing other potentials, seeing a new path to follow. It’s sometimes called learned helplessness and can be hard to deal with alone. Becoming antisocial (not wanting any human interaction) is also usually a difficult thing and is usually caused by a personal neuroticism. But we need purpose as humans, and we also need comradery quite often.

Thinking of yourself as a collection of habits can be helpful for this. You should be asking yourself what exactly makes you upset about about other people, and try to relate it to something about yourself.

You can’t change other people, but you can change how you react to other people. Quite often that requires a shift of perspective that acknowledges that you are a biased viewer enterpretting a limited view. Instead of “people talking about themselves are annoying” for example, “I am bothered by people when they talk about themselves” can be more useful. That way, you are talking about the emotional response you have to others rather than the perceived traits of others - your lense is now focusing on you instead of on others.

That’s all I’ve got. The path to being content is difficult, and I wish you luck.