For all his charm, good looks and charisma, Keanu remains a Hollywood Bachelor. Being happily single myself, I don't see anything wrong with that.
Some people just aren't ready. Some will never be ready.

Now, I'm not going to say that Mr. Reeves is not "marriage material", but here are a few reasons that it might be better that he remains happily unbetrothed.

• Leaves used floss and q-tips all over the bathroom sink
  
• Plays bass in his sleep.......at full volume.
  
• Insists on keeping an annoying answering machine message sung to the theme to "Bewitched"
  
• "If you're married in The Matrix, do you have to sign a 'pre-nup' in real life?"
  
• Already committed to pre-arranged marriage into the House Harkonnen, for the good of the Empire.
  
• Potential mates put off by the fact that he waxes poetic about urination.
  
• Irrational fear of big cakes and cheesy DJs.
  
• Worst. Morning. Breath. EVER.
  
• Has over a dozen "same time, next year" arrangements across the globe.
  
• Picked his own square in the Dogstar bachelor pool.
  

I imagine he has his reasons, and they probably aren't so complicated.
One thing I'm sure of, it's not for a lack of willing candidates.