I was this way most of my dating life, and I don't think there is anyway to stop getting high hopes when you are attracted to someone. I think that if you just decide not to rush things, be patient and get to know the girl a little, you won't make any foolish mistakes or assumptions which could ruin things. Start slow; like ask her to go for coffee, then if that goes well try for a longer date like a dinner. I think a lot of people make the mistake of having the first date run on too long, or going to a movie where you are not interacting and staring at a screen. That way if you aren't hitting it off, you are stuck with seeing it through. Hope that helps!
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Dreams are renewable. No matter what our age or condition, there are still untapped possibilities within us and new beauty waiting to be born.
-- Dr. Dale Turner