Why the ignorance about me being a Republican from Dems/libs?

I live in a fairly liberal city..well a VERY liberal city. 65%-85% of the city is a Democrat, depending on what section your in. When ever I tell someone I'm a Republican, they automatically ume I'm a misognynst, anti-choice, phobic, racist person. My neighbor is a huge Obama supporter and lib and when she said she was going to a rally in favor of comprehensive education I asked her where it was because I would love to tag along. She looked at me with the BIGGEST WTF face I have ever gotten. So I said "you know, instead of uming I was some right wing extremist and blowing me off 99% of the time, we could have become quite good friends over some issues we agree on." My social views are mixed with conservative and liberal viewpoints - my liberal ones are I'm pro-choice (but do support the partial-birth abortion ban), education and birth control access, and support for gay marriage & adoption. I'm conservative in more social areas (gun rights, affirmative action, immigration, etc.) but I hate that stereotype. I consider myself a fiscally conservative, socially moderate, foreign policy hawk Republican, aka the true blue East Coast Republican.