Anyone know how to deal with feeling unwanted ?

Eat urself. jk. you don't need to be in a good social situation. If you want to change you should do it for yourself not because of other people. A lot of people don't have a social circle and don't need one just because a lot of people do. Talk to people that you like and make your own circle of friends. If all else fails, you can move to a far away place where society is different and social situations are different.

there are lots of things you can do, love goes in many directions. Your situation right now involves your father, write him again and say sure there were things he missed but there are more things in your life to enjoy together, that you still have a full life ahead of you that in the future involve education, a career, driving a car, a long time from now but needing him to help you choose a mate when the time comes, and needing him to walk you down the aisle, and be a grandfather to your children, and then say so you want to start now to know him, know that he cares about being part of your life. People who already have their life and career and such have children themselves and offer concern and sharing and such to their children, and to their spouse, and some people wrap themselves up in the work the love, or in volunteer work, or even by getting themself a pet. Later in life it's not all about feeling unwanted but in getting out there and giving to others like helping out where needed in babysitting or watching an elder person or feeding the poor at a facility, or teaching catechism or just simply reaching out to (make) friends because when you give you also receive.

go to a lounge or bar and have a drink. that will loosen you up and feel a little more confident to talk to women and approach people.

Take a class of something you like to do. say if you like to dance then take a dance class. you'll run into people. also try to strike up a conversation with someone.

You won't get a date unless you get out of that comfort zone for awhile. Assert yourself more.