Unless you're making plans to meet or have met this isn't really dating. I understand you can get invested online, that's how I met my partner, through online gaming. But we at least were physically talking to each other first. But we didn't count it as a relationship until we had been in each others physical presence a few times.

Have you skyped, or video called?
Just be careful, I know it can sweep you away and become like your just sitting waiting for those messages to come in.

As for your friend, You can't really afford to let yourself get tied up in this emotionally, especially since you can't really do anything to help.
Being there to talk to is great, but you can't be responsible for someone's welfare, in this situation.

All the best, take care.