A moment of selfishness

Flying home to SFO from MSY and it was a packed flight.  A petite Asian teenager finally walked up and politely asked to step in.  As I stood up... she asked if I can swap with her mom (coming up behind her) who was sitting one seat behind me.  Who am I to separate a mom and her child? 

I did a courtesy turn of the head and saw who I was going to be sitting next to.  SCREEEEEEEEECH!!!! Hit the brakes!!! Hold up!!! Waaaaaaait a minute. 

I paused long enough for the mom to come up now and ask the same question... if I can swap with her.  I turned again to look at my potential neighbor.  Turned back to face the mom.  Turned back to check out the dude.  Turned back to face the mom.  

Then I hesitantly, in a loud whisper told the mom.  "That guy is very wide.  This is a 5 hour flight.  I can't sit next to him."  

I already have limited leg room.  That guy was big, wide, and muscular.  I've sat next to big people in the past and to no fault of their own, they intrude into your personal space.  And there's literally NOTHING you can do about it.  Either you rub up against them.. or you try and bend your body away.  But for 5 hours.....??? I can't.  I can't!!!!!

I felt so bad... in that moment of selfishness.  But I'm not wrong... am I???