Spoilers ahead
The last 20 minutes of Interstellar are as confusing as confusion gets. I would like to state my interpretation and put the question then.
My Understanding:
Based on a blog post I read (which has since been deleted), it is postulated that a spinning black hole can be used as a wormhole itsel, which I believe explains Cooper's arrival at the tesseract in the movie.
Regardless, once he is in the tesseract and has conveyed the message to his daughter Murph, there is a dialogue between him and TARS where TARS says that the plan seems to have worked as the bulk beings are closing the tesseract.
On closure, Cooper and TARS are spat out near Saturn (miraculously, maybe) where the Cooper Station finds them.
Questions:
Why would Cooper Station be orbiting Saturn? Why not just jump through the wormhole to the other side?
Does the closing of tesseract also mean closing of Wormhole near Saturn?
If the wormhole is closed, where does Cooper, in the very last scene, think he is going?
Anyone's guess is as good as any other. But a rationale explanation would be truly appreciated.