Affiliate Marketing Secrets

hi, i am 20 and when i was younger i wrote this diary account sort of thing of my life – which was not a conventional one lol and it’s come to about 150,000 words – which is longgg. ive been scrolling through it now thinking how crazy i was as a teen and although i wouldnt want to publish it as it is now i have taken bits out of it to make chapters based around the same happenings.
i would like to publish something from it actually just because there are bits of it i am proud of creatively and i would like to communicate some of the messages in there to young people. i am on about 40,000 words, my issue is, it’s kind of in a biography style while i explain my life style in the past tense but then i like to go into the present tense when i am using a lot of dialogue and going into the scene – as if i am looking back on the time and the reader can get drawn in to what is ‘presently’ happening. can i do this though? i don’t think i’ve ever read a novel which does that, does it like defy the laws of authorship or something?
Also i have no idea how to go about seeing if i could publish it…it will be a novel surrounding mental illness and the behaviour of young girl who immerses herself in a dangerous life at night, whilst still at school, she escapes the madness via a loving relationship which becomes abusive and i am unsure how to end it because the situation is still open…so it’s based around the truth but to make it interesting and less painful to write i’m going to fabricate some of it…but i don’t know what market to aim this at and if i should bother at all…it feels like it could be a bit self indulgent and like no one wants to read about any of that anyway…but writing is the best form of therapy i have found, anyway i would like to hear opinions! the possible titles i have come up with so far aree ‘Secret life of a Cambridge school girl’ (pun on ‘secret life of a london call girl’ – because it’s a similar story), ‘Stockholm Syndrome begins in London’ or ‘Becoming Dolly’ – which focus’ more on the abusive relationship part of the story. anyway, any advice would be greatly appreciated. thanks, Laura