Looking for some help

So there's something I've been struggling with lately and I can't figure out what to do. So I thought I'd write about it here to send it out to the blogosphere and hope for some responses. My problem basically boils down to the fact that I've been tired a lot lately and have a really hard time getting myself out of bed in the morning. I'm a relatively healthy person, and I may even be in better shape physically than the average person (I did just run a marathon!). So why am I so tired? And most nights I'm getting around 8 hours of sleep (there are some nights when I have trouble sleeping, but they don't occur that often, and it's usually just the first few hours I'm in bed, and not all night). So I always have great plans when I go to bed to get up early and workout or get other stuff done and I set my alarm and it goes off in the morning and I hit the snooze button. I've never really been a consistent "snoozer" so how did I get myself into this habit, and more importantly, HOW DO I GET OUT? The last several years I haven't been that fond of winter, so could this possibly be something that is caused by winter? To be totally honest, I'm not opposed to counseling, but I also don't want to jump into that if it's not necessary. Any ideas on a simple way to get myself out of bed in the morning and not hit the snooze several times (I do know that's not quality sleep I'm getting while "snoozing")? I did sign up for a spinning class at my gym one morning and got up when I needed to for that. But that won't work for every morning. Can anyone help?