Those three words are probably my biggest annoyance. Here's a piece that's been running through my mind for days, it doesn't come from anywhere in particular, or anyone. However, it can be applied to so many things that happen in our lives.
How could you? Why would I? You should have. If you would have. I could have. Why should I? How could I? Why should you? I should have. You could have.
Those three words usually come about after the fact. When its easy to place the blame, placate our guilt, or regret things you should, could, or would have done. It may be pride, anger, pain, or other things that are holding you in the pattern of those three words. I'm not immune to them, and being a creature of habit, it's hard to change.
Life is too short to let those words rule your life. Reach out to those you should have, where you could have, and perhaps they would do the same. Quit making excuses, and get out there and do it. Change those three words to: shall, can, and will. Be it interpersonal relationships, your home, or yourself, change those words. You just might change yourself.