Yep. The first time he had thrush he was about 6 weeks, and it lasted a little over a month (because the nystatin didnt work!). Then he started getting patches again around 8 months, I gave him the Gentian Violet when I first noticed it and it was gone within 2-3 days, then it looked like he might have the beginnings of white patches again when he was about 10 months (after he was on antibiotics and also had a yeast diaper rash) so I treated him right away and he hasn't had any problems since.
If you only treat yourself, and she has it, even if she has no symptoms you two will just keep passing it back and forth between the two of you.