Turf Valley is lovely, but it's sort of in the middle of nowhere (i.e. not served by public transportation) and staying there for an extended period won't hold your interest unless you're a serious golfer. I'd opt instead to base yourself at a hotel in downtown Baltimore or Washington, cities both well-served by and connected to each other with public transportation.
That way you'll only have to hassle with arranging transportation to/from Turf Valley once rather than every single day.
There is an airport shuttle servicing Turf Valley to/from BWI Airport charging $35 ($29 first person, $6 each additional) each way. (http://www.theairportshuttle.com) I suspect a taxi connecting downtown Baltimore and Turf Valley would run at least as much.
I'd check with your hosts to see if they know of another guest staying in downtown Baltimore who might be able to help you out with a lift to the wedding.