My bread keeps coming out dense (help? Advice?)

I've tried several different recipes. Even got a book about the science of it all. Can't be too rough, can't knead too long, but must knead enough to activate games. I started doing this as a past time and now this is just so damn frustrating. Im not trying to make fancy bread I just want delicious bread to consume when I want a sandwich or when I want toast in the morning. My husband also likes to enjoy the occasional carb. But I like to make white bread, your basic go to. And yet. I swear. I do everything exactly right. Exactly as the recipe says. It either doesn't rose enough. Or comes out really dense and sponge like. It really deters me from wanting to make more because as much as I hate food going to waste. This spongey texture then turns hard as a rock in two days. Making it impossible or even good to eat again. What am I doing wrong? What am I not doing? What am I possibly doing too much of???? On rare occasions I do make nice airy bread. And i have no idea how I did it.