I don't blame her either. I hope she goes on to be in a lot of movies. She is a great actor. Honestly cable networks need to get a grip on the schedules. If they'd allow actors more freedom to work on multiple projects, they probably wouldn't have such an issue with keeping cast... remember back in the 90s when they'd just get a completely different actor and pretended like nothing happened?
For the longest time you were either considered a TV actor or a movie actor. TV was your stepping stone a lot of the times, but with the movie business not being what it use to be, and streaming services upping the ante on quality programming, I think that line has become blurred significantly. There is no reason someone can't do movies while on a show. I get the whole exclusivity to a single show while its running, but I think you could keep actors more content if they were allowed to obtain multiple income sources from extra projects. I bet it would severely cut down on contract disputes when performers aren't limited to one pipeline of bread and butter, and on the flip side it might save some smaller studios money. Bigger actors may be more inclined to take a role with lesser knowns giving those companies a boost perhaps? Pure speculation as I'm not very knowledgeable about the acting industry. But with all the petty actor and writer guild strikes over the years, they all seem to take place while the industry is at a high point with several successful properties running.
As for TWD actors not being in anything else, some find other work or will.. maybe not in the most notable ways.
Lennie James does voice work for Destiny, he was in the last Blade Runner film, but before that he was briefly in the terrible 1998 Lost in Space movie.
Norman Reedus was undoubtedly the most established actor when the series started having been in Blade II, Boondock Saints, and Pandorum. He'll have no problem finding work after, and hes already in Death Stranding as the main character.
Laruen Cohen was practically unknown, only doing soap opera cameos, and TV show guest appearances. Oddly enough she was the Stranger in Destiny 1. Now I want to meet her at a Con and ask her about all the lines she had that never made it in to the game.
We'll probably won't see Andrew Lincoln for years if ever. I think he's made his money and wants to spend the rest of the time with the family. He'll probably do commercials and con appearances.
Melissa McBride is another great actor, I think she might pick up a role or two, but shes def one of the older actors. Her first work was Matlock and Heat of the Night. She did some Walker Texas Ranger, and I'm going to have to find that TNT movie Pirates of Silicon Valley.. I loved that film, and didn't know she was in it.
Danai Gurira already has a spot in the MCU, I know she'll find work, shes done very little before TWD, but I think she's got a bright future and this will be looked back on as her breakout role.
Steven Yeun probably won't go on to do anything big in psychical acting, but he is well established in voice work. He's done American Dad, Trollhunters, and Voltron.
Seth Gilliam previously did work on The Wire, Oz, Starship Troopers, and The Cosby show, He has 3 projects listed on IMDB already. He'll always be a side character, but will always probably have work because he is good at what he does.
Josh McDermitt and Christian Serratos will probably wont be in much else outside of cameos.
JDM obviously will always have work and is the most established to come on the show since Norman Reedus. Hes just a solid actor and has the look of a big star. He was in Ramapge
Steven Ogg will always be typecast as a perpetual shitbag, because damn, he is good at it. His work as Simon was excellent, he's also a host in Westworld and was Trevor in GTA V.
Obviously Jon Bernthol found his role as the Punisher. I can see him picking up a few more lead roles here and there.
David Morrissey is an outstanding actor but will probably always be on British TV only.
Michael Rooker is always going to have work because of his unique voice. Whether it be voice acting, or a villain role. He was great in Guardians of the Galaxy.
But all those other characters like T-Dog, we'll never see them again. Emily Kinney does her music thing, and I wont be sad if we never see Chandler Riggs ever again.