I can offer you a little advice from the chicas:
1. Wash your stinky gear and occaisionally take a shower.
2. Don't even think about asking for a shuttle unless you plan to return the favor.
3. Show up with a cooler full of cold beer at the takeout.
4. Load her boat on top of the truck. (not because she can't, but because you can).
5. Don't forget that she was already boating before she met you, so keep your advice to yourself.
6. When you are sitting around the campfire (most important rule), don't act like Mr. Badass! That's usually a turnoff (especially if you are not).
That pretty much covers it. Lots of Betties out there, but most of the boater dudes just can't handle number 6. Maybe that's the problem???