At most, they might at some point discover their latent and repressed nature. Yet, they were born like that.
There are some people who don't even realize they are gay/lesb, or repress their feelings because of social pressure. Again, it's not like a change of mood.
If I exposed you to gay porn for a whole month, do you think you would become attracted to men ? If you really think that, then you must be feeling insecure about your own sex. But it's a very different kind of problem you have. Perhaps you are a closet gay and can't come to terms with what you are, and you are afraid of yourself. You know, sometimes the most virulent haters of gays are closet gays. They don't accept themselves.
It's obvious that everything that challenges your beliefs makes you very uncomfortable. But it doesn't change reality.
Then I hear that we need to protect the children of the sight of gays, because they are so easily influenced and could become gay. Very poor excuse.
You could as well be saying Look I am a very tolerant person toward Blacks, Muslims, Jews or gays but I'd rather not see any. And it would be good if they could pretend they are not Blacks, Muslims, Jews or gays when they mingle with us.