Flocke, Jacob, Aaron. All are one and the same by Aarushi

What do MIB and Aaron have in common?

A Crazy Mother.

This was a huge revelation and it instantly made me think: MIB is Aaron. Perhaps the island keeps repeating the same events time after time, generations after generations. So MIB is born again - just like him and a lot other people probably have, again and again for thousands of years until it "ends once" only to start the cycle all over again. And this time round he wants his new generation self to grow up with a NOT crazy mother, hence changing the direction of things and end this iteration of life the island is causing. I think he spoke to Kate at that precise moment about the crazy mommy because he wanted to make sure Kate left the island with Sawyer, leaving [his] crazy mother behind. This also makes me think that he is sincere in his promise to Sawyer about letting him leave the island. He probably even knows about Sawyer's big plan to leave with Kate on the Sub. The Smoke monster has demonstrated before that he can read people after all. He wants Sawyer to take Kate o! ff the island who will take care of the new him, ie, Aaron.

But how do we explain the lack of physical resemblance with Aaron? Firstly, we cannot be sure that the form we saw MIB in by the beach with Jacob was his original form. Secondly,I am getting more and more convinced that Jacob and MIB are the same person: multiple personalities of Aaron. Jacob and Aaron do indeed look similar. Maybe before this timeline, Kate never took Aaron so he grew up with Crazy Claire in the crazy island. By the time he grew up with all the craziness, he developed a multiple personality disorder. That's why MIB and Jacob cannot kill each other: because they are the same perso.
So, infact, like many have been predicting forever, mabye Jacob IS Aaron after all.

Maybe this time things change and we see a healthy Aaron grow up into an adult who looks like Jacob, in a normal house, outside of the island. He visits old mommy Kate and daddy Jack/Sawyer (probably Sawyer) and they all reflect on the time they spent on the island.

Or, a lot more likely, I can totally see lost ending with no one else in the island but a little baby Aaron in Jacob's cabin struggling with himself...producing an arch nemesis within himself, waiting for the island's iteration to start all over again...

That's it. This is my first theory ever, hope you like it!
Aarushi