This idea has definitely been done before, but you've done it justice. I loved the line, "her act wears thin and cold," and the choice of verb reflects the thinness of her act -- wasting away, unable to escape. I liked that.

However, in the fourth line, you wrote "the mascara YOU wear," which is fine and grammatically correct, but that was the only time in the poem that you used "you" as a subject; the rest of the time, it was "she." Intentional: yea or nay?

Also, you might want to consider grammatical divisions for an easier read. To sum it all up, good poem, but take care with the editing and formation. :)
~Cristina

PS: Am checking to see if you have more poems posted. If so, will read.