grammar - What is the し particle and how do you use it?

I understand that obviously every Japanese textbook will go into this topic briefly... but I can never really come to grips with what it means in Japanese. If anyone could link me to a good Japanese dictionary entry about it that would be great (I can't find a good one that explains it)

I am interested in the し particle as used below... 歯は痛いし、歯医者には行きたくないし、困ったよ。

I was wondering if the し particle had anything to do with する/しか/しも.

職場は失うし、妻とは別れるし（で）、彼はひどく元気がない。 Here, it seems like し seems to turn the reasons into some sort of noun phrase because the author has stated you can use で with them.

Knowing the essential underlying meanings behind ので and から helps me to unconsciously decide between them... I kinda have no idea how to do the same with し so... Can anyone enlighten me or link me to somewhere where I could be enlightened on the matter?

Answer

し is used here to create a list, and I'd translate your example sentence as "My tooth hurts, I don't want to go to the dentist... it sucks." (lit: "I'm troubled")

It's sort of　like や in that it creates a list, but as I'm thinking about it, し is used more for a list of reasons that culminate in a conclusion stated later in the sentence. I might describe my girlfriend as follows: 頭がいいし、かわいいし、日本語を勉強するし、お互いに話しやすいし、本当に好きだよ。

Here, I'm listing out various reasons I like her. In your example, you're listing out reasons that you're troubled. Hope that helps!