Absolutely keep bathing her - it helps soothe them and wash away the germs. Just make sure the room is warm and toasty (especially as it's getting colder these days - my bathroom is drafty!) and you dry her off and get her dressed and snuggly ASAP. The vapor baths others have mentioed are great! The best thing for a cold is lots of rest and a bath helps them get there.
And news for the lady in the grocery - my 3-yr old started pre-school in August and it seems he has a cold or some other bug way more than before he was 3, I don't think it ever ends, really!
Finally read your baby and if she seems really uncomfortable, feverish, if you felt that way, would you want to go to the library for storytime? If you think she might do better with staying at home with warm snuggles from mommy, then skip the library. Runny nose but otherwise good spirits? Snuggle her up and head out if it makes sense.
GOOD LUCK!