How often were you playing out in those 30 years?
My strings get drenched with sweat every show, and I guess I'm fairly heavy handed as well . Only broke one playing fingerstyle, broke a bunch playing with a pick.
I actually broke an A stirng on a quiet acoustic type gig a couple of weeks ago.
I'd love to be able to throw a new set on every week, but I don't have the budget for that. I'm lucky to get a month or 2 at the most, out of a set , and that's soaking them in denatured alchol after every other show. If I don't they're shot after two shows, sometimes one. As in the E and A are completly dead and lifeless, like an old set of flats.
This happens with every bass I own as well, so it's not an issue with a bridge or anything. Usually after about a month or so, they're flapped out to the point where they break.