I've been working from home for a year now. I don't get out and see people often, my family live far away, so I don't have many opportunities to see people in person. The exception is, my brother is staying with me while he studies at University. There have been a few periods however where he's been away up with our parents, or off at a different university in a different state. I have a few friends I talk with regularly online through IM, and it helps, but the periods when my brother was away were still very difficult and I was getting very stressed towards the end, even though we don't interact all that much on a day to day basis, and even though I've always been much more tolerant and even thriving on loneliness than most people I know.

Maybe video chatting with people would be an adequate substitute? I haven't tried that, but my anecdote is that IM / talking online alleviates some of the stress, but goes nowhere near to mitigating it.