Whats up with my birth father?

We've been in reunion since 1984.   His family believed I was someone else's baby.   When I met him it was obvious that was not true.  Because my birth mom is Lebanese, and I turned out looking like him, was the smoking gun!  hahaha!

So I send him a Christmas card every year, for the past 12+ years.  This year I got it back in the mail. Says  "Return to sender" - "Attempted - Not known"  "Unable to forward"  -  this means he picked this one piece of mail out, and handed it back to the mailman I assume he probably knows.  He is the only person living in this house and has lived there for about 29 years.  My aunt, his sister, was just there last week!  ha!

So why would he do this?  He is friends with my oldest son on Facebook.  And I unfriended him, but he requested to list me as his daughter!

Anyhow, its somewhat of a rhetorical question.  Or should I say its more of a million dollar question? 

I don't feel bad, not really.  I'm curious.  And what I really want from him is, a DNA test.  To once and for all prove that yes, he is my biological father.  Something that seems fairly logical to me.  I have never asked him, because I really know what he will say.

I've never asked this man for a single dime, and he's really not gone out of his way to have anything to do with me or my family.  He really has nothing to do with my brother either.  You can safely say he is not winning any father of the year contests.

I blurred his full name and address, here is the envelope.  My youngest son said to send him a Harry Potter load of mail, overwhelm him with a ton of mail!  I wouldn't waste my time.  I may send it again, and to be honest, I was expecting him to do this for some reason, and was looking in the mail every day for this exact thing!  Sixth sense?  YEP!