Rebecca Mader reveals she's leaving 'Once Upon a Time' after season 6 -- and it wasn't her choice

It's been a week of casting bombshells for "Once Upon a Time" -- and fans aren't going to be happy about this one.

Just days after leading lady Jennifer Morrison announced her departure from the show, co-star Rebecca Mader revealed in a lengthy Instagram post that she too is leaving. However, there's one big difference between the two: While reports claim Morrison left on her own, Mader is making it clear that she got the boot.

"A lot of you have been asking if I will be joining everyone in Season 7, so I wanted to let you know personally that unfortunately I am not," she said. "This wasn't my choice but a creative decision of the shows that I totally respect and understand."

Mader has played Zelena, The Wicked Witch of the West, since the show's third season.

Although it hasn't yet been confirmed, reports are swirling that Ginnifer Goodwin and Josh Dallas will also be exiting the ABC program. The only actors officially returning so far are Lana Parilla, Robert Carlyle and Colin O'Donoghue.

Although her post expressed disappointment, Mader isn't holding any resentment toward the cast and crew: "I am truly happy for you all and most importantly for the fans that will get to keep tuning in each week to see where they take us," she wrote.

See photos from ABC's "Once Upon a Time"