The use of the word "Gay"

Today, I was surfing my Twitter page, and I found a tweet from...well, that's not important. The tweet included the word "gay" and it wasn't used for what it really means; it was used to describe a person who is afraid of doing something.
I don't have a problem with the person who tweeted it. In fact, I look up to that person, and it just really surprised me to see "gay" used the way it was used in that person's tweet. It was almost derogatory, and maybe it was.
What's wrong with that? In my opinion, when "gay" is used to describe someone or something that people don't like, it can be offensive. You'll never know when you describe something as "gay" and there happens to be a person around you who is gay and may take some offense, and they won't say anything about it. Using the word "gay" as an adjective for something that sucks, something that isn't good, or someone who isn't good, something that people don't like, or someone that people don't like, implies that gay people suck, aren't any good, and aren't liked.
This case is exactly like that of the word "retard". It should not be used to describe something that isn't liked because it is offensive. If you're using the word "ritard" with and "i", then that's a different case because it's a musical term that means "to slow down". There is a movement called Spread the Word to End the Word, which is a movement to encourage people to stop using the word "retard". To stop using the word "gay" should also be a part of this movement, and maybe it already is. I'm not sure, but people should be encouraged to stop using those words because they can be derogatory.
I know people are entitled to their own opinion, but people need to stop using "gay" the way it is being used today. We just don't know how many gay people are brought down and belittled by just describing something as being "gay". It might even be contributing to their depression or thoughts of suicide.

XD