For example: if it's not nice, don't say it. I'm not telling everyone to suck up to everyone, but find a nicer way to talk about something that might be hard to discuss. Weight, never talk about someone's weight. Everyone is sensitive about some aspect of their physical appearance and I would guess a large percentage have weight issues. If you're concerned, make sure that you're close enough with that person to discuss the topic. Say something like "hey, a while ago you said you might like to start taking walks, want to try that out together?"
That right there is supporting the other person's fitness goal without saying "get up and walk fatty, your couch is sinking!"
If you find it impossible to come up with a nicer way to say something, look at yourself. Think about why you can't say things nicer. Were you raised with parents who constantly criticized you or other people? Are you deflecting your own insecure feelings? How would such a statement feel to you?
If you find a problem within yourself, no need to worry or freak out. Simply try to think out your responses and comments before you say them.
No offense. That's just bad manners. By saying "no offense" it shows that you do in fact know this is a touchy subject, but hey, say it anyway! Nothing nice ever comes before or after the statement "no offense."
If you find yourself receiving such negative remarks, look at yourself. Are you being too sensitive? Did the person mean well? Did they offer assistance?
Always stand up for yourself. Maybe not immediately, but think for a minute, then respond. It's ok to tell someone that they've hurt your feelings. If you don't say it, they'll continue to offend you. This can lead to broken relationships and loneliness.
If you feel someone is being too sensitive, always check the facts. What did I say? What did he/she say? What was the context or overall general feeling to the conversation that led up to the negativity?
Energy Vampires will be sure to continue the negativity. They will suck the energy out of you until you explode. It's ok to banish people from your life. It's ok to give second chances. Make sure you're true to you, and you are able to share your love without harm.