Meg, ask if they can provide (or if they already will be providing) a salad for you. If possible, you can either bring some lunch meat (or whatever strikes your fancy) to put on the salad or you might be able to use some of their protein if it's one of those pasta bars where you add your own protein and sauces to the pasta. Try to get more info and let her know what your needs are. I know how hard it is to make a fuss and bother people, sometimes, but I've never run into anyone who is frustrated or upset with me for asking for help with my diet.
Most people (especially women) totally understand and are very accommodating.
That said, I'd bring an appetizer that's easy for you to use as a main dish, if you have to, like 3-bean salad, or the shrimp you mentioned, but bring a veggie dish for yourself to help you fill up.
Like Barb mentioned, if you're on Phase 2, you can have Whole Wheat pasta. See if they are willing to try making one of the pastas whole wheat! With the new food pyramid out, a lot of people are starting to focus on eating whole grains and they may appreciate the chance to try it! If you are on P2 and they won't do whole wheat, ask if someone can ensure that one of the pastas (and remembers which one) is made from Durum Semolina (whole, not enriched). You can have that once a month on P2...it's the same as regular pasta, just high quality. That oughta fit in for a gourmet club!
Bring your own sauce or ask if they will have Pesto, Bruschetta, or a pasta pomodoro...any of them are SBD safe, usually.
There's tons of ways around this girl...and I'm glad you're thinking that way.
Like Sandi's sig says, "If you want it, you'll find a way, if you don't, you'll find an excuse." Good job "finding a way"!