I have swings like this as well. I've been in a stooper the last couple days and cannot pinpoint exactly where it may be coming from. For me, I feel it may be stress related. I've come down with a cold and in my weakened state, my body is craving the self-medication of PMO. Being sick and being at work brings added stress which I'd like to believe is what has impaired my general optimism.
I've noticed as I work on recovery how many triggers I really have. It used to be just physical things like tv shows, pictures, or girls walking down the street. Now feelings and emotions, coupled with physical triggers, really flare up unwanted urges.