How to deal with topping urges while locked

I've recently started identifying as a submissive, after having identified as a switch for years. I came to the realization that in perpetual D/s dynamics (such as the one I have with my wife) I'm submissive, and for me to identify as a submissive just "feels right" for lack of a better explanation.

However, I do still have strong sadistic inclinations, and would have no problem of really topping someone for a limited time-span - like an evening session, a day or maybe even a weekend.

Now, my problem is thus: in the past, whenever I'd get these sadistic urges - either from watching porn or just because they sometimes pop up out of nowhere - I'd go with them, culminating in me jacking off. Being a submissive in full time chastity, I can't do that anymore.

So how do I deal with these urges when they come over me? I'm sure there are others out there that have had similar issues to overcome in the past.