True words, but I think this is not as easy as it sounds. I think you have to differ here between how you act in public and how you act between people you are more close with (Maybe I am already too influenced by Japan!? lol).
Also it depends on the reason why you are emotional moved. But I think the worst thing is, if you hide everything from people you are close. On the other side I also can understand that you maybe don't want to be a burden for anyone, so this makes it hard again.
In general I agree with what you have written, but it is sometimes hard to realize. But it's easier if you know that you have people who want to help you and who don't see you as a burden. Then it's much easier to open up.
RE: If you're grumpy and you know it, stomp your feed!