Slouching is NOT cool

I'm wearing a posture brace right now. It's a figure-eight brace that goes around my shoulders and to my back. It's not particularly comfortable, but I suppose it's not supposed to be. It's not terribly uncomfortable, either, so I'm wearing it while I sit at the computer tonight. In fact, it'll become part of my nightly ritual. Truth be told, it's been sitting on the floor next to my bed for a week or so, silently judging me every time my shoulders hunch.
Why the fuss all of a sudden? I've noticed over the last several months that my posture has become less and less straight. I've never had the best posture, and I accepted that, but lately, I feel like my back is actively beginning to hunch. This bothers me, simply because I refuse to be one of those old women who is all bent over and creaky. I will not have Sydney look at me like I'm at all weakened.
So, the brace. I understand that it won't be the ultimate savior. I know I need to do more exercises for my core. I did my research and found all kinds of things to do.
Now, it's just a matter of doing them.