Glass

His  heart is made of glass. Whether it looks half empty or half full. It all takes up the same amount of volume. Sometimes he pours or drink too liberally. He's quickly inebriated, hopelessly intoxicated.
He gets excited, when in his drunken wisdom, thinks he knows what it was. But then, clumsily trips over some careless words that were left on the doorstep. He drops the glass and it shatters, leaving wet stains which could be confused for tears.
It's alright because similar to him, it's part of n interchangeable set. We can always buy more at the shop, if the store runs out, they can always order more from the factory. They build them on site, in their workshop.