Simple and direct:
* I ended up eating the whole pizza myself.
* After getting lost, we ended up at the wrong park.
Expressing an unexpected outcome:
* I was planning on going to the movies, but I ended up staying home and reading.
* We thought we would be gone for a week, but we ended up staying for a month.
Describing a final state or condition:
* The party ended up being a lot of fun.
* Despite all the challenges, the project ended up being a success.
With a prepositional phrase:
* I ended up at the library, even though I wasn't looking for a book.
* They ended up in a lot of trouble after breaking the rules.
With a gerund (verb ending in -ing):
* I ended up running the whole marathon, even though I wasn't in shape.
* She ended up apologizing for her rude behavior.
Using a different tense:
* I ended up eating too much, and I felt sick.
* They will end up regretting their decision.
* He had ended up losing all his money at the casino.
Remember, "end up" often implies an unexpected or unplanned result. It can also be used to describe a final state or condition after a process or series of events.