Conflict

Humans aren't perfect. We stuff up, we make mistakes, we upset other's, we piss people off.
Most people are going to upset you at some time or another, and it's very easy to take it personally or assume the worst.
But as the saying goes, when you assume, you make an ASS out of U + ME.
So we can do what we think makes things better. We can go and retaliate with equal force, we can be sneaky and talk about them behind their backs. We can be passive aggressive and bring the topic up in a public forum, where without mentioning names the blame is obviously being dealt on the other.

Or!.... We can talk to that person from a place of love. We've all done it. You have something you want to tell someone and it comes out all wrong, or you tell a joke and it isn't understood. Maybe you were doing what you thought was the right thing and never thought to ask the person how they felt.
It's so much easier to clear up conflict and confrontation with the individual you have a problem with if you just go up to them and say "hey, I noticed you seem a little upset/angry/hurt/*insert emotion here*, is everything okay? How can I help?" Or maybe it's the opposite, "hey, remember when we were talking about the dishes/that dress/the party/*insert upsetting topic here*, well I was a little bit upset by what you said and I just wanted to let you know, because I'm sure you wouldn't have wanted to hurt my feelings and I want to work this out"

Yes, it seems cookie cutter and cheesey, but how are you supposed to solve a problem you have with someone if you aren't upfront and tell them what's going on?
We're all only human, and 9 times out of 10 it's based on a misunderstanding that is easily resolved and often laughed at when actually spoken about.
What's the worst that could happen? They admit they wanted to hurt your feelings and you manage to get a toxic person out of your life? Or maybe you realise you were the one with harboured resentment and hatred?

Talk about it, get it solved and move on.
There's no point waiting for the other person to read your mind and hope it magically gets fixed without actually trying to fix it maturely.