Lay it on Thick: Origin and Meaning

If someone ‘lays it on thick’, they make an emotion or experience more important or serious than it really is.

figurative

Jane is at home, packing things in to a suitcase.
There is a knock at the door.

Jane: Who is it?
Simon: It’s me.
Jane: Go away.
Simon: Open the door, Jane.
Jane: No.
Simon: Oh come on Jane, I think we should talk.
Jane: About what?
Simon: Us.
Jane: I don’t want to talk to you Simon, it’s over.
Simon: Open the door Jane. Stop being silly.
Jane: I don’t want to talk to you Simon, please go away.
Simon: But I live here, I have nowhere else to go.
Jane: Alright, alright you can come in.
Simon: Jane, I can’t stop thinking about you, I miss you terribly, I can’t sleep, I can’t breathe, I can’t live, l can’t even dream. Look at me Jane, I’ve lost weight, I’m a wreak. Please, I beg you, come back to me.
Jane: Ok, ok, don’t lay it on thick.