Please remind me I'm doing right by my cats

by not letting them outside no matter how much they beg.

They're used to having a little outdoor patio and in my new place, there isn't anything. (There's a side yard that cannot easily be fenced in/netted off.) There are lovely big windows and lots of light and things to look at and fresh air coming in, but they want to be *outside*. It's not a super-busy street and there are other (domestic) cats that roam, but I just feel ... if I let them out there, I may never see them again.

ah, it's breaking my heart...