Despite my subliminal program I wrote (and no its not subliminal. drop it!), I'm having trouble LD'ing lately.

I dream, but remember at best one dream a night. I go to bed being very determined and confident that I'll have an LD, but I stay 'stupid' through all the dreams.
Usually I'm much better at it than this...

There could be multiple reasons for it, but was wondering what you guys think is the biggest possible reason:

1) Its a cold, dry, dark winter. I wake up feeling tired. Lie in the bath and fall back into REM. I almost feel as if my delta sleep might be longer in the winter perhaps.

2) Lots of work stress. The company is going through a massive change, and contracts are being rewritten.

3) I stopped my dream journal.

4) There's no ventilation in the room in winter.. cos.. well, I'm not leaving that bloody window open.

Thoughts?