Our rear wheel bearings seem to be getting loud, again. With only 152K miles on the car we have replaced rear bearings twice already at a cost of $1200 each time. We don't tow anything and never carry more than a 50 lb sack of dog food and rarely have even one passenger in the rear seats. Are the factory bearings just a poor quality part? Could I use aftermarket USA bearings and do the job myself? 

Has the car ever been wrecked? 
Rust?
Alignment good?

Definitely do not install any aftermarket bearing.  They fail all the time, no matter what brand. I can't exaggerate what garbage they are.  Anyone that says "I used this brand and didn't have issues" has replaced very few wheel bearings, so that's why you'll find "success" stories if you look.  Anecdotal.  At scale, aftermarket bearing suck. 

*Except in instances where aftermarket companies use OEM parts just to fill their catalogs.  So sometimes you can buy an aftermarket bearing and receive an NTN/NSK Japanese original OEM wheel bearing.  But that's inconsistent since companies can change that from year to year.  

Replace only the bearing that's failing - do not replace both bearings in pairs if that's what is meant by "we have replaced rear bearings twice".  

Modern wheel bearings are more prone to failure, I have no idea why. but it's wasteful considering older bearings didn't fail as often. Even Honda's have more wheel bearing issues than they used to.  It's the new normal unfortunately. 

$1200 is kinda steep for a bearing job.  These newer style cartridge bearings are easier to DIY since you don't need a press.  Probably your biggest sticking point is loosening/tightening the axle nut.  Look up some videos and decide if you can do it yourself, it's quite possible.

It's probably about $200 in tools.  After that you can do a practice swap with any el cheapo $50 bearings, then go oem $150 bearings later.  You'd still come in under $1200.