I don't feel that you're wasting our time. You sound like you're in a difficult situation and I think you have every right to be upset.
You seem very isolated, and I know, that's not an easy thing to deal with. It's a very painful thing to deal with. Especially when you desperately want to reach out to others, but can't, due to anxiety or fear of rejection. It can be so, so painful, to need something so desperately, but to feel like it's constantly beyond your grasp.
I meant it before, when I said that social contact is a basic human need. It's normal to want other people to care about you. And it's normal to feel upset when you can't meet that need.
Sometimes, when a person is alone for a long period of time, they can start to doubt their self-worth, they can start to feel that they don't deserve other people's time. But I don't think that's true, I think you do deserve to be listened to. You do deserve social contact. And you do deserve fulfilling relationships.
By the way, if you're not comfortable posting here in the forums, then you might find it helpful to talk to a listener instead. They sign up specifically to help out with problems like anxiety, depression, or even loneliness. It might take a few attempts to find a listener that really 'gets' you, but most listeners will be very happy to hear from you.
You don't have to talk to a listener, and you don't have to talk to us, but remember, the option is always there if you need it.
I'm going to keep on checking this thread, in case you choose to reply. I hope you do.
P.S. Good luck with your appointment.