I'm glad you said that because if I'm being honest I didn't know what the hell was going on at first.
I think the lady with the torch is Kelly/his true love. The scenes with the other women represent him fucking up either with other women or alcohol. She's always been there, watching it all happen from the sidelines, trying to pull him out of it. He wanted out of his debauchery, but couldn't stop even when he wanted to (which I got from scenes where he gave her looks of desperation/sadness). She finally gave up and was going to kill off any hope (her jump into the lake symbolizing killing their relationship). But at the last minute he realized what's important- her. So he finally made an effort saved their relationship.
Or maybe the torch lady isn't directly Kelly. Maybe she symbolizes whatever/whoever was good in his life. Or she could be the symbol of his own hope for things to be better.
My thoughts exactly, but you'd have to be a pretty hardcore fan to get that I think. To the uninitiated this is going to be well confusing. It's cool to use metaphors and arty acts and situations but the point is a bit hard to get. It's still great just a bit unclear whereas for instance a similar song like Scars, the 2nd video was clever and got the point across so diectly and more than likely added to the immense success of that song. Totally unrelated but BID is ten times better than Scars because Scars gets a bit repetitive, BID is killer.
Also, WDTAG vid is awesome. Simple and pure rocking out, love it.