Always remember that... YOU MATTER!
Unless you apply Einstein's: E=MC^2 and multiply yourself by the speed of light squared....
Then... YOU ENERGY!
Disclaimer: There is, as yet, no conclusive proof that certain in-laws, out-laws, or ex-partners are exceptions to this rule; and should be referred to as "you anti-matter" or "you darkmatter"
Einstein is apparently still working this one out.