I completely understand where you are coming from, but I agree with Candeke, you should probably just back off a bit and try to schedule in time to talk. The hardest part about maintaining a relationship through online means is that you can't see the person and what their life is like for real when they don't sign on. So it's very easy to start thinking all this stuff when you also don't get face-to-face time. You are gonna meet up with him, and he'd not have agreed with that if he wanted to back out of the friendship! So it is probably just real life for sure.
I am the type of person that is always online either on my macbook or on my phone. So it was hard for me to understand how you could not have time to log on and talk. And I would take it very personally. But in the end, it probably wasn't. Some people are like that others forget about 'the internet' for days at a time. You can't get me to forget for longer than 30minutes