My best friend has withdrawn into himself and eventually acknowledged that he is depressed. He's always been rather elusive and rubbish at remote communication, and lives about an hour away, so it took me a few weeks to notice. I think this has been going on for at least a month, and I suspect stems from stuff in his day to day life exacerbated by very long-term family issues (we've been friends about 25 years). He is self-employed so it's quite likely he hasn't been leaving the house much at all.
He doesn't want to talk on the phone, doesn't want me to visit (we usually meet up every couple of weeks), but in one of his very rare replies has said that my supportive texts are helpful. He's not a great texter at the best of times so I'm trying to limit myself to one or two a day, maybe jokes or film recommendations, never requiring a response. I'd usually only text him maybe once a week - our conversations are usually only face to face - but if he's not talking to me he probably isn't talking to anyone. I'm texting more often because I'm desperately worried and I want to make sure he feels loved and supported.
Am I handling this ok? Are there any helpful/unhelpful things friends have done when you've been in a similar situation that I should consider doing/avoiding?