former weightlifter turned triathlete repeatedly breaking hanger
The way you asked the question, it sounds like you think the following is happening: first, the derailleur hanger wears out/weakens, then it snaps, and this causes the derailleur to go into the spokes.

It is much more likely that the chain of events is the following: the derailleur is mis-adjusted, when you shift to the largest cog on the rear, the derailleur goes into the spokes, and this causes the derailleur hanger to break off.

Possible causes:


the inner limit screw on the rear derailleur is too far out, needs to be tightened a bit, until it reliably keeps the derailleur from moving too close to the spokes
the chain is too short, and when you shift onto the largest rear cog and the largest front chainring (not recommended in general), the chain gets too tight and this rips off the derailleur.