Dated January 15 1995 and written from prison, the Hit Em Up star's letter gave an insight into his relationship with the Material girl singer, then 37.
Appearing to explain why he called time on their relationship, Tupac explained: 'For you to be seen with a black man wouldn't in any way jeopardise your career, if anything it would make you seem more open and exciting.
'But for me, at least in my previous perception I felt due to my 'image' I would be letting down half of the people who made me what I thought I was', the rapper, whose mother Afeni Shakur was an active member of the Black Panther Party activist group wrote, adding: 'I never meant to hurt you.'
'Can you understand that?' he added.
In 2015 Tupac's brother Mopreme Shakur confirmed Madonna's claims that the pair had dated, revealing that it began with a 'passing of a note' during the star's Above The Rim press day in 1993.
But by the time the letter was written in 1995,things had clearly taken a turn between the A-list duo.
Keen to give his side of the story to the apparent breakdown in their relationship, Tupac's note began: 'I've waited a long time 2 finally write this.
'Mainly because I was struggling to find all the answers so that I wouldn't leave any unanswered questions.
'First and foremost I must apologise to you because like you said I haven't been the kind of friend I know I am capable of being,' he said of their relationship, thought to have started
Appearing to address a public media feud, he continued: 'An interview where you said 'I'm off to rehabilitate all the rappers and basketball players' or something to that effect, those words cut me deep, seeing as I'd never known for you to be with any rappers besides myself.
'It was at this moment out of hurt and natural instinct to strike back and defend my heart and ego that I said a lot of things.'
With another section blurred, the Rose That Grew From Concrete poetry book author continued: 'Can you feel me?
'In the time since, as you can see, I have grown both spiritually and mentally.
'It no longer matters how I'm perceived. Please understand my previous position as that of a young man with limited experience with an extremely famous sex symbol.'
And appearing to want to make amends, Tupac went on to offer an olive branch to the hitmaker.
'I offer my friendship once again this time much stronger and focused. If you are still interested I would like to further discuss this with you but some of it couldn't wait.'
Proving his caring side, the political rapper added: 'PLEASE BE CAREFUL MADONNA.
'Everyone is not as honourable as they seem. There are those whose hearts bleed with evil and envy'.
In an ominous message Tupac, who had previously survived being shot five times, but was gunned down a year and a half after the letter was penned, added:
'They would not hesitate to do you harm let my five bullets be proof of that!'
'Ps If there is any information you can share with me regarding Jack and crew please do, it could well be a matter of life and death.