Have you thought of exposing yourself to activities and social situations a little at a time? For me it was starting grocery shopping in the middle of the night and going later and later each week.

I would suggest making yourself plans to get out and/or doing something over gradually increasing occurances. My therapist had me always make two plans to choose from. It's easier to say I'm not going to do one but harder to say I won't do both. This really did help me.

What supports do you have in your area? Even though school is out there should still be some mental health supports at your college/university. All the better if you could talk a parent into going with you. Call up your GP. The office may be able to help you out with an out of usual hours appointment if this would be helpful. If getting to and from appointments and supports is an issue your local mobile crisis or mental health association should be able to help you with that.

Stay in touch.

I know how incredibly debilitating Depression is at this time of year. It is usually my hardest. But, over the last 6 months I've worked dilegently on my anxieties - which I believe are related. As unbelievably hard as it is the answer for me was to get out. It took babysteps to be sure but it has paid off.