You know, I "have a husband" too. Does she actually live with/have a relationship with this husband, cause why else would she say "I'd love to." Something's fishy about this, because it seemed like she was hitting on you just the other day. This deserves investigation! I bet she's still technically married and afraid to date anyone while she still has that label. WEIRD.
I know exactly what you mean, but I really don't think that's the deal. She made it crystal clear that she'd really like to but couldn't. I didn't get any impression at all of "and that sucks so much because my 'husband' is a boat anchor," (and I am unfortunately all too familiar with that nuance), just "I really like you, it's a damn shame I'm taken."