Gun haters hate guns for one reason.
You were close.
Gun haters hate guns because the gun represents power that they know neither how to wield for themselves, nor handle the threat they represent.
They were not taught how to handle any kind of real responsibility, and they know they are too impulsive to avoid overreacting in the face of a threat.
Not that they have ever been a victim of violence - they just fear it, and they fixate on the gun as a symbol of it.
Instead of learning how to properly use a gun to counter criminal threats, they want all guns gone.
They can handle all others.  They just verbally beat down the threat.  They are quite adept at tearing down other people.  I have only met a few people with liberal beliefs who did not practice this type of response to a challenge.  The rest have an inferiority complex, and must tear others down so they feel like they have a purpose to life, and so they feel like something other than what they really are (and they know it) - powerless.
It took me quite a while to figure this out, but I simply looked at the whole lives of most of the antigunners, and found that their whole lives really sucked.
I have met a few people who didn't like guns because they had been in contact with violence with guns as the tool, in some form or fashion.  The above holds true in a modified form, but at least there is a reality basis for their beliefs.
In any case, they can't handle power, either to use it properly for their benefit or to counter it, and they need to be led.
Now the LEADERS of the antigun political groups are another story.  They want control.  They want power.  They are socialists in humanitarian's clothing.  They have a vision for a perfect society and it doesn't have any room for you or your guns.  Want proof?  Read the Communist Manifesto, then compare the language of communism to the language of progressive liberal gun control.  The leaders are evil and they will stop at nothing to acheive their vision of a perfect society.