As weird or hard as it sounds, you need to embrace being alone. That doesn't mean you shouldn't try to expose yourself to situations where you meet people or think about how you spend your time (may I suggest: limit internet/computer time). It just means you should enjoy the positives that come with being alone and avoid seeing it as a shameful thing you need to distract yourself from. Other people in other circumstances never get a chance to be for themselves and have the reflection and thoughts this allows for. You are with yourself and that is hard and frightening, but also a chance to come to terms with yourself. From your description it is pretty clear thst this is probably something you need to do.

Get something to care for, plants for example. If you need inspiration on a deeper level consider watching Perfect Days by Wim Wenders. Don't read too much about it before. It is one of those films that gave me a new perspective on things, may it do the same for you. To find joy in the simple things and go through your day in dignity.