*You need to stop enabling her, and to give her notice and timelines of you expect X by Y, which are long enough to get her to save cash to move out or whatever.
DH did this with the two DSD's. One of them stayed with us for a bit and I suspect they thought post uni he would be an ongoing cashpoint for them. He told them he would help 100% with rent for 6 months after graduating and then tailing off to 25% and then 0% by a year, and the same with phone contracts etc on the expectation they'd have found work and housing to support themselves
Before each major change in contributions to them, he gave them fair warning (~2 months) each time there was a change coming up, enabling them (or not) to manage finances appropriately. He also offered to help with CVs etc in the run up in case it helped. *
This sounds like absolute GENIUS.
If you and ex DH could get on board with this, and fund this, it removes the choice of whether to leave home or not, without feeling like you've tipped your adult offspring out onto the street.
But the reality of having to find a way to provide for themselves is crystal clear and time defined.
I'm assuming it's made clear that at the end of that period, one option that is not on the table is moving back in with a parent. . .
You do have to do something drastic, because with her in the late twenties, she's fairly embedded in your lifestyle to which she enjoys being accustomed, and she feels entitled to it. She's not going anywhere soon without making major changes. And at late twenties with no real and significant work history. . . um, it's not just biological clocks that start winding down. . .