Flats are random events...unless there is a underlying mechanical cause like rim tape or failure to remove the puncturing object. Others have covered this. I'll cover technique.

You say that 2 flats came from 'hitting decent-sized pothole(s)'. Therein lies some of your problem. You aren't particularly heavy but you can still do damage to you tires, tubes and wheels if you don't ride properly. Hitting a pothole hard enough to cause a pinch flat says to me that you are sitting on the saddle like a sack of potatoes and letting the bike take the impact. You need to ride 'light' in the saddle by using your arms and legs to absorb the shock of impacts. You don't 'sit' in a bicycle saddle like you would a chair. You hover over the saddle most of the time and when you see an impact coming...you should be watching for them too...you lift your body up and used flexed arms and legs to absorb the impact. Your body's suspension can provide several inches of travel and allow the bike to bounce upward on impact so that the wheels don't take the brunt of the hit.

I'm a lot heavier then you and I ride bikes with lower pressures but seldom experience pinch flats. That's because no matter what bike I ride...mountain bike, road bike, commuter bike or loaded touring bike...I always ride light in the saddle. I even jump mountain bikes and seldom set down with a KERTHUNK! because I let my arms and legs absorb the impact.