Bh I have been clean for 190 days most of those days I had no access to internet. Now I am home and I have full access. May god help.  my question for you is my motivation not to watch porn is the fact that I want to start dating  in the next year and I want to be "pure" for my wife.  is that an unhealthy motivation?

Excellent motive. Pornography corrupts and destroys the true picture of love intimacy and sex in marriage. Besides being pure, you will want to be a giving selfless husband. Stay far far away from porn and you will be the best husband you can be. Hatzlocha buddy and may Hashem help you find the right one easily.

I think this is a great motivation. Are you saying it's your only motivation? 
What do you mean you have full access? Is there some way for you to get it filtered or blocked? Or to speak to the powers that be and explain to them that you really just don't want access, or that you want to use the Internet only when someone's around, etc.? It would be a shame to lose the winning streak you're on, and having unrestricted access is so great of a nisayon.

How long of a clean period do you think I should wait before starting to date? I know its probably a hard question to answer.

You definitely appear to be clean long enough to date. Howeveryou should find yourself a mentor to speak with to help make sure you start the process correctly. The "sur mei'ra" you have bh done. Now lets get the "asei tov" right.