+1...just what I was going to say; get in the shower with them after every ride!!!
Funnily enough...
Actually, I too only own a couple of pairs of padded shorts, so they, along with my jersey get washed out in the bath or shower after I've done and then dry overnight on the line.
Mind you, I only commute 2-3 times a week by bike so it's not so bad. Doing it this way, they only go through the washing machine once every couple of weeks.
I do have to do this after ever journey though, the longest they've gone in when I rode to work, took the van home, used them for MTB that evening, then commuted home in them. Wouldn't want to have pushed it any more than that and I'm glad my commute is very rural
Works for me though, my original LIDL cycling jersey is still going strong after over 3 Years of use! I'm guessing it's because it's not over exposed to harsh detergents and I'm pretty sure I don't smell (he says, hopefully)