Re: I need mature advice.
You've tried having a relationship with him twice now, and it didn't work either time, and unless the reasons the relationship failed before are no longer there, then it doesn't really stand a chance of surviving a third time.
You come across as being very mature for your age, but having said that you are still only 16 and who you are now is most likely not the person you will be in even 5 years time. You haven't had experienced life as an adult yet and neither of you should be thinking of long term commitment at this point, especially when its already failed twice.
My advise is to go with your head as the heart is easily fooled.