People continue to disappoint and confuse me

So I made friends with this engineer at work.  I know I go on and on about being lonely here in my nowheresville town, but it is true.  I sit alone way more than is healthy.  So when I met this guy at work who is very nice, we became chatty (at work only).  

Then, he began telling me about some problems he was having at home with his wife.  Then he tells me they are separating.  She moved out of the apartment and took his son to live about an hour away.  Then we end up at the same social event one evening and chatted some more.  Now let me state this now, I AM NOT INTERESTED in this man romantically.  I have my boy and this guy is not really my type.  But, I am interested in being buddies.  I need friends and he seems nice and interesting.  

One evening a few nights ago, he called me and asked me to dinner.  He then said, 'just as friends you know.  this is not a date."  PHEW! We are on the same page.  is what I thought.  So we had dinner, it was uneventful.  Borderline boring really.  All the while, this guy is also hanging out with my neighbor.  But I get the feeling that they are more than just friends.  Which is totally cool with me, except they are putting me between them (what did she say about me?  What did he say about me?) But that is mildly annoying and mildly amusing at the same time.  

So yesterday he calls me and asks me to come hang out with him and his son in the evening.  I agree. He asks me to pick up beer on my way.  So I do.  When I get there, his son is snoozing and we sit down and he proceeds to down the entire 6 pack in the span of 1.5 hrs.  Then he tries to kiss me!  GROSS.  he was so drunk and dumb.  So I made some excuses and was out of there by 9pm.  He continued to text me until I turned my phone off at midnight.  His texts were apologetic at first and then turned belligerent and then pathetic.  I did not reply to any of them. He knows about DJ, so I don't know what his deal is.  I thought he liked my neighbor.  

How do I look at this guy tomorrow at work?  I just wanted to be friends and have some local folks to hang out with?  Why did this blow up in my face?