...For that reason, my husband has been using the kit lens, but it's horrible in low-light/indoor situations.
Which kit lens? If you mean the 18-135mm (which I own, BTW) or 18-200mm, I'm not aware of any constant f2.8 (or faster) zooms that cover that range.
However, if you mean the 18-55mm, on a crop sensor 60D, in addition to the Sigma lens Jiko mentioned above, you could also upgrade to Canon's 17-55mm f2.8 for around $1,000. (I also own a copy of this lens.)
Or if even f2.8 is too slow, Sigma also makes an 18-35mm f1.8 which is obviously shorter, but in addition to being more than a stop faster, also costs a bit less (around $800). (Full disclosure: I own one of these, too.)
Other than that, you'll have to switch between f2.0 primes and risk missing the shot.