ADHD or just a jerk? :-)

My boyfriend and I dated 19 years ago for a year.  We reconnected in late 2011 and discovered we still feel the same way about each other.  We had a tumultuous 2012 due to his entanglements with his ex-wife (divorced 8 years). After a 9 month separation (he's east coast, I'm west), he called, and we've had the most amazing last 2 months.  Long talks about everything we've been through.  He calls me the love of his life, his best friend, the woman of his dreams, etc.  He told his friends, neighbors, and co-workers I'm his girlfriend.  He had me talk to some of them on the phone.  He texted every day.  He made sure I knew I was his girl.  

We've discussed my moving there.  We had every challenging conversation a couple should have before making big decisions (money, past relationships, habits, trust, friends, faith and values, on and on).  He booked a trip to come here, and I booked a trip to go there.  7 hours before he was supposed to get on the plane, he picked a fight and didn't come.  He emailed me the next day to say he would call, he just needed to calm down and clear his head first but loves me.  That was 2 weeks ago - I sent him 1 very benign "hey do you still want me to come visit you?" email a week ago which he ignored.

His life-long coping mechanism has always been avoidance (and secondarily lying because he always feels he lets everyone down so he'll say things like he broke his phone if he forgets to call).  Neither of these has been a deal breaker for me.  I've had some challenges in my life, and I understand having not-so-great coping skills - although mine are a lot more functional than lying and running! :-)  But he's the love of my life, too.

So, advice from those with more experience . . . . could this disappearance be an ADHD thing, or is he just a jerk?  Could he really have just been overwhelmed by the idea of making our relationship "real" by coming here, meeting with my counselor, and having dinner with my friends (both of which he said he was happy to do) that he panicked?  Could he be overwhelmed by something else in his life, and he knows he hurt me and can't deal with me AND whatever else is happening so he is ignoring me?  

I know he loves me.  That's not the issue.  And I know he'll eventually call - he always does.  I just don't know if his actions can really be attributed to ADHD and therefore I can learn to understand and cope, or if I'm just fooling myself into thinking he's a good man with issues when he's not.

Thank you!