How long to get over him/her?

I feel like in any generally good relationship that ends, there will always be feelings towards them no matter how long the relationship was. The real question is whether you can learn to accept these feelings and be able to not be affected by them.

As long as it takes...

I was in a very close relationship for close to 30 months, was close to getting married.

She left me over her own insecurities almost 4 years ago.

I guess I haven't gotten over it because I still care for her. (Haven't seen or spoken to her in 3 years)

But... I've learned how to deal with it and I do not let thoughts of her affect me.

It all comes down to understanding your own emotions for the other person. Once the lust and infatuation subsides it's easier to rationalize your emotions and understand that while your feelings are not openly reciprocated, it's ok to still have feelings for the person and go on with your life.

theirs no specific time.
it varies in the person
and how the relationship was going.
the person who got dump feels the worst so its harder for them

It took me two years before I stopped crying daily about him. It was a mutual breakup and now four years later, I realize it was for the best, but it took me a loooooong time before it stopped hurting. Good luck. Learn about yourself through this process.