I’m found in a kiss, lost in a fight, and broken in a word. What am I?

What I contain often pales in comparison to what my potential entails. I can be anything your young imagination can bring, so don't break me down or recycle me, please?

Your brain on illicit chemicals, if you watched MTV in the nineties. A little milk at the beginning may make me fluffy, but do not add the salt at the end. Like an omelet, eggs are beaten together; but unless they are stirred in the pan, the outcome will change.

I stand so still, yet work all day, Giving little gifts away. Push me once or wave hello, Watch my tiny treasure flow. I never eat, I never drink, Yet I help more than you think. Some say I'm kind, some call me neat, I make small jobs feel quite complete. Sometimes I'm found beside a sink, Sometimes where the people drink. Sometimes I live upon a wall, Waiting proudly, straight and tall. I never ask for gold or pay, But serve a hundred times a day. A gentle press, a careful squeeze, I do my work with perfect ease. I have a mouth but cannot chew, I open wide because of you. I have a belly full inside, Holding all I safely hide. Sometimes bubbles, sometimes cream, Sometimes sugar for your dream. Maybe soap to clean your hands.

I grow heavier with every drink. Yet lighter with one squeeze.