What Supergirl comics do you recommend I read?

When I use to collect comics,  Supergirl was always so convoluted.......first she dies, then she comes back as some  shape shifting alien.....then that thing dies, and she comes back as the split personality of someone else-------- like whatttttt????? 

They just kept messing up her storyline, and reinventing her too many times. 

I'd stick with the ones before she actually died,  in the Infinity Crossover series. 

Back when she was just Supergirl......the REAL, one and only Supergirl. 

I'm not usually a Supergirl fan but I did enjoy what I read of Supergirl by Peter David.