Things change as we get older...for good or for worse. It's what we decide to do with those changed things that makes the difference.

If she just isn't "feeling it", it just means she isn't feeling it. It doesn't mean there's something wrong, just that it's not the same as it was.

Feel grateful for what you have. Happiness is in large part a matter of perspective. Do something nice for a friend or neighbor and the feeling will come back.

She's stuck in the Christmas rut. The same usual things you do every year. My suggestion is to do something for someone who really needs it. Volunteer at a church Christmas event or adopt a child to get gifts for etc. maybe just bake goodies for a local elderly home or such. Sometimes just doing something for someone and seeing the magic of Christmas through their eyes will help. It will also make her realize all the wonderful things she has to be happy about. This down feeling happens to just about everyone.

Do something sweet and Christmasy for her. Like....plan a night for just the two of you. Bake cookies together, drink egg nog by candle light with Christmas music on. And give her a gift early. Nothing special, but a nighty would do the trick. I'm sure you can help bring light to her Spirit.

There's something called Seasonal Affective Disorder which is when the winter months bring on depression. It's usually caused by the time shift and gloomy weather. I have Bipolar and I know I get depressed most of the time when it gets to be winter.

That said, just because she's not into Christmas doesn't necessarily mean she's depressed. It could just be that she's growing out of liking it. I don't really much like Christmas, so I can understand where someone could grow out of enjoying it.

If you think it may be a serious case of depression, you may want to talk to her about seeing a doctor or therapist before it worsens.