All That I Want

I am red,
but sometimes I am black.
I can make you happy,
but I can also make you sad.
I can make you smile,
but I can also make you cry.
I can love you,
just as much as I can hate.
What am I?

The black heart was made by =fooble182 Hooray! I wish I knew how to make one
_{When I was Looking through my gallery the other day I came across this ->[link] It's scary how much I have improved, So I have decided to do the new version of "Love me please"}