If you want to get some spiritual intelligence back, then you should, at least for some time, separate yourself from the object of your lust, purify your conciousness with increased chanting and prayer, and then decide with a clearer perspective if this is the person with whom you actually want to spend the next 25-30 years of your life in joint service to Krishna. What value will there be in your life if the only basis for making a decision for engagement is that you've found a good sex partner? That won't last long, I assure you.
Collected Letters Written to Friends and Disciples Vol 4, Pg 35, 4th Paragraph