Re: I need mature advice.
It may sound romantic to get back together, but reality is not a fairy tale, and childhood sweethearts very rarely stay together.
At 16 years old no-one should be expected to make a long term commitment to another person, and your boyfriend seems too immature to cope with an adult relationship and commitment. He may think he's ready now as he's not ready to be without you yet, but he's not ready to be with you either.
The chances are you will only end up hurt again, for the third time, and at your age you have a whole world of choices still ahead of you.