[¯|_(ツ)_|¯]

I think it's worth trying to write on this website, and if it doesn't work for you then at least you've tried. Writing things out can definitely be a huge help for a lot of people.

If you're worried about people finding out maybe you can start out by removing identifying information that could hint at it being you. For example, you can say the country you live in since there's loads of people that live there, but maybe until you get more comfortable you can avoid using the city name, especially if it's a small city. If there's details that need to be included to make the story understandable, you can try to be vague (such as saying "I live in a city near the woods/ocean/etc.")'. Since you're worried I'd definitely also use a different username or a fake name that you haven't mentioned anywhere before.

I don't think your friend will think you're copying her if she finds out, but if she does send her a message you can say that you saw her post saying writing has helped her and you found it inspiring so you thought you'd give it a go too.

Sharing the website here is fine as long as the sole purpose of your post isn't to advertise the website, the website isn't a competitor of ours, and you use the appropriate trigger warnings when sharing it.