How many miles were on your t-belt when it broke? What year 850? Was the t-belt replaced before at the proper interval or did you decide to skip that?

If a new serp (aux. belt) belt broke causing that to wear through the t-belt housing and thus also destroy the t-belt (my understanding of your story here?), something must have rubbed the new serp belt to cause that as they usually last a very long time (serp belt, 60K mile replacement interval).

If you failed to have the timing belt replaced when it was required, then you'ld only have yourself to blame.

I'm seeing ALOT of cars lately where customers are choosing to skip replacing their t-belts (apparently thinking it's not necessary or lacking funds) SO it'll only be a matter of time when many more t-belts break and that's unfortunate as it's very costly to repair, about $3,000 US.