I'm in the same boat. All friends and family use iMessage. But why does that stop you from switching? Granted it's easier to use iMessage when everyone else uses it but shouldn't SMS/mms work fine (although it sucks compared to iMessage).
Oh it does just that they refuse to use other messaging methods. When asked I get reasons like oh I want all my messages in one place, or I don't want to swap services or I don't like other messaging services etc. All very frustrating.