If you can't be there.. don't. Stop telling people that you will be there, It's better to tell people the truth up front. That way you can spare some feelings and you don't get caught in a bunch of lies/trouble.
If you have something to say.. say it or shut it. Don't go behind peoples backs. There is no reason to say it to someone else if you can't tell it to the person it's about.
If you want it.. go for it. Take a risk. Don't always play it safe or you'll die wondering.
If you love someone.. let them know. Anything could happen to you or the person so tell them while you have a chance. It could change everything.
If you're stuck.. make the best of it. There is obviously nothing you can do so whining and complaining isn't going to do anything-there is a difference between expressing how you feel and complaining. Put forth your best attitude and you just may get out of the mess.. possibly with a different perspective.
If you're troubled.. take time to think about it. Nothing good ever comes out of rash decisions. If it's important enough to trouble you then it's important enough to think about-think deep you'll figure out something.
If you're being taken advantage of.. let go. Get rid of all thoughts of the person. There is no reason to continue to surround yourself with the person who is taking advantage of you.
If you're going to criticize someone else.. admit your own mistakes first. Everyone makes mistakes. But be aware of your own before you point out someone elses.