Picture people as Gobstoppers; a jawbreaker-type sucking candy with several layers.

The Gobstopper that represents me is a disgusting mess.
Bitter layer after bitter layer.
I feel like every person in my life that has disappointed me has added to these layers.

If I had to make a detailed description of the taste of this metaphor, I'd have to say that the center and last layer is sweeter than the rest, probably tasting like grapefruit. The middle layers are unsweetened tea. And the first layer...

It tastes like envelope glue.