Hey WL,
Everyone has so many great suggestions. I've been experiencing 'runaway brain' lately at night as well and have restarted the nighttime herbal tea drinking (in the afternoons).
This time of year and the weather change just puts me right back into times other than right now. So I have to pull out all the stops. And tea bags. At night I remind myself that torturing myself by thoroughly examining a painful thought is not going to change an outcome from the experience.
Ditto the sentiment of being gentle with yourself.