I don't use social media such as Facebook to socialise, though there is a private group I sometimes post in.
On forums such as this one I rarely socialise, I usually just post in reply to a thread, but sometimes someone talks to me via PM. I'm happy for people to PM me and appreciate it when people take an interest in me, though this doesn't happen very often. I'm too shy to start conversations with people, and don't do so unless I have a specific reason to do so.
Occasionally, I talk to someone who PMs me on Skype or via email. I've made a couple of friends this way, though usually they last a month or so and then fade. I tried a chat group, but most of them are a lot younger than me, have certain interests which they have in common but I don't share, so most of the conversations are around these interests, there's a lot of banter and it goes too fast at times, this is normal for chat groups, I think, so I often feel the odd one out and that I don't fit in.