I've been working from home for a year. I'm an introvert, but I think loneliness would've set in by now except for some fortunate balance in my setup. My wife and baby are in the house most of the time (not so much that they interrupt, but enough that I can hear noises when they're around), I meet friends for lunch at least once a week, and in the evenings and weekends I do other things besides code constantly. I thought I'd need to get out to cafes more for a change of pace, but so far I haven't needed to.

Everyone's social needs are different as relates to mental health, but my recommendation is if you don't have family or roommates around making some noise and conversation, keep an eye on your how you're feeling and set limits on how much of the week you toil in isolation.

It can also be bad for your health if remote work relationships are difficult, so you have to have a certain amount of company support for what you're doing as well.