Is he cheating?

I have been with my current bf for 8 months now, long distance (2 hours away). He was diagnosed with ADHD with some OCD symptoms.  I honestly can accept his certain traits of ADHD, because I grew up with a ADHD brother.  I saw the worst, my brother couldn’t sit quietly in the class and was violent towards his classmate when he was angry.     

We used to see each other twice a week, then went down to two times a month, now we only saw each other 3 times in the past two months.  He was attentive when we were together, bought grocery before I came, added gas for my car and we didn’t have any problems with intimacy.  He was quick to judge, but if I told him that I didn’t like his comments, he would apologize!

However, I have this feelings that he is cheating, at least emotionally.  I read articles about the cheating of ADHD is related to attention disorders or distractions.  I wrote him two emails telling him what I didn’t feel comfortable of what he was doing, never got replies and he kept doing what he did.  On the normal dating forum, all those are big no no, but since he did have ADHD, so I listed some his behaviors below for the experienced ones to tell me if there are any problems and if all those are ADHD related:

  1. He never answered my questions about what he did or where he was.  Or he said he was at work, but he checked in Facebook somewhere else.  He got frustrated if I persisted, and I hated confrontation, so normally I dropped it off once he showed signs of agitation.
  2. We don’t text each other often, sometimes I went for a week or two without any news from him.  I texted him once or twice in between to check on him but never got replies.   On the other hand, when we were together he couldn’t put down his phone, constantly texting or emailing, sometimes even during the night.   And he always said he texted his friends.   His phone is not password protected though.
  3. He unfriended me on Facebook when we had the first argument and told me he would add me back on later but never did.   He went to Philippines for a 10 days vacation without telling me, when he came back, there was a photo of him with another girl.  His post was not visible for public, but he featured that photo so everyone could see.
  4. He had history of addiction to dating apps, it affected his working performance as a result.
  5. My name on his phone is a sexual innuendo.  There are no more sweet talks between us, but criticizing or complaining about what I do.  On the other hand, he needed constant reassurance from me that I didn’t see others behind his back.  
  6. The planning of dates was getting worse.  He didn’t actually forget, but he would change all the time at the last minutes on the days I had to travel.  Not to mention all the broken promises I assumed he forgot.