Don't be a jerk. Say it nicely.

We've all heard it a million times:

It's not what you say, it's how you say it.

And we've heard it a million times, because it's true: you really can say most things, sans drama, as long as you say it (all encompassing - body language included) nicely.

So, next time you've got your grumpy pants on with your lover, why not do what my aunt suggests: wrap your arms around them and say: "Darling, it really gave me the sh!ts today when ____ happened, BUT, i do love you just so much" then kiss, kiss. 

You've kept it light and made your point. 

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