I don't understand girls...
Allow me to take an evolutionary biology perspective on this matter.

At any given time, women of high desirability have a multitude of potential suitors. Though different women and different men may have different tastes of partners, let's face it, if you like one girl then chances are many others want her as well. There are baristas of Starbucks whom are asked out no less than ten times a day. To further complicate the matter, unsuccessful suitors take form of male friends; they all either secretly want/would want to screw her or she wants/would want to screw them, depending largely upon who initiated the friendship and timing, as sexual attraction is the primary impetus towards such matters. So, women have many suitors whether or not realized.

Multiple suitors have the evolutionary advantage of mate selection by natural selection. Weak suitors don't survive and by the constant, gradual adding in of new potential suitors, whom either survive or die, certainty of the most fit suitor is resolved. You were voted off Survivor Island long ago but since you had kept up the interest to keep the connection, she figured she may as well capitulate and use it for what it's worth: drugs. People will use you only as much as you allow them.