This is such a complex and long history: there is no simple "back story" and the "result" has not been decided. With the 20-year rule of this sub it is impossible to truly get into the resolution of The Troubles and the current situation in Northern Ireland.

/u/girlscout-cookies gave a great answer to this topic in another thread. Could anyone give me a brief, modern history of the conflicts between Ireland, Northern Ireland, and the UK?

If this does not answer your question then please let me/this thread know. Once you have the framework then the finer points you are interested in will be better answered.

It's quite a long story, but it looks like you just want the general gist. /r/explainlikeimfive would probably be the better subreddit for this question.