This text is here because discord likes to preview part of the post, and I do not want to spoil you here. Instead, if you wish to see my theory for how house of cards ends, click on the link above.
Not sure how long this has to be, but lets go for broke and write quite a bit out, before I reveal.
In the UK series his wife kills him to save him from a career destroying scandal.
Claire will kill Frank. And become President.