You're
Giving her everything that I wanted. Everything you said you'd be giving me–and all of these things that you've done to me,
You'd never do to her, or them
Could never be done to her, or them
And it's crushing me to think about
You & her, and them.
You have everything & I have nothing.
I have nothing at all & the weight of *that* is crushing.
The weight of nothing.