What to call it when someone takes something the most negative possible way

Is there a word for the situation when someone takes something said in the most negative possible way, basically stretching what is said to fit the negative meaning that they desire it to mean.

Example:

"Maybe we shouldn't hang out."

to mean:

"I never want to talk to you again, you are cut from my life."

Solution 1:

I'd call it pessimism. Or even extreme pessimism.

Solution 2:

I think that "melodramatic" would work well here.

Characteristic of melodrama, esp. in being exaggerated, sensationalized, or overemotional.

For example:

Dave: I can't come with you on Friday.

Lynn: You never, ever want to see me!

Dave: Oh, don't be so melodramatic!

Solution 3:

I feel the most appropriate description of this situation is over-reacting or over-reaction.

Solution 4:

A common way of describing someone who always exaggerates the downside of any situation and/or chooses to interpret everything pessimistically, is to say...

He/she is so negative.