What I mean is that since Alice ended its run in 1985, Linda Lavin has been a main cast member of three additional sitcoms: Room for Two (https://en.wikipedia.org/wiki/Room_for_Two_(TV_series)), Conrad Bloom (https://en.wikipedia.org/wiki/Conrad_Bloom), and Sean Saves the World (https://en.wikipedia.org/wiki/Sean_Saves_the_World). All three of them didn't last any longer than a single season. I'm assuming that she stuck with television since her film options were decidedly limited (she didn't start appearing in feature films until The Muppets Take Manhatten in 1984 and has only appeared in a handful of feature films since then) and Broadway presumably doesn't pay as well as television or film.

Did Linda's age play a factor in her not being able to better capitalize off off her Alice success? I mean she was I believe, almost 40 when she first got the role. So there's a good reason to believe she was unlikely to ever obtain a similar role again. And then there's of course, the rumors of her being difficult (http://discussion.femalefirst.co.uk/viewtopic.php?t=234248) to work with and running Polly Holliday and later Diane Ladd off the show, since they served as rivals to her attention.

she got work. she still works!!!

I think she preferred to work on stage, and spent most of her years focused on that.

Since those 3 other sitcoms failed, maybe she had enough. She still did well for herself though. 9 years on a successful major network sitcom. It's debatable whether the show went on for too long, but she had a pretty damn good run.