You could say: * "She's everything that's ever been." * "She's everything that ever existed." * "She's all that has ever mattered." * "She's everything from the past."

It depends on the context, but here are some alternative ways to say it: "She’s everything that ever existed." "She’s all there ever was." "She’s the beginning and the end." "She’s everything that matters." "She’s all that has ever been."