Search Results: should i leave him marriage

-Background Info (skip if you want):
So I have known this girl PB (super cute and sweet) for almost a year now, but never talked to her much in HS. She's INCREDIBLY shy & would actually get scared of anything. She would pull her arms in tight or twirl her ponytail hair whenever she got nervous. It was frickin' adorable.
Anyways, I didn't see her but once since the end of school last year. Fast forward through a summer and 4 months of college to today. I came back during her gym period to talk to her again. Now she is SUPER friendly & open to me, waving as I came in and asking all sorts of questions later. This is weird for her because she's usually super shy. We talked along w/ her friends. I climbed up on the bleachers siting right next to her, touching leg to leg & arm to body (breaking the touch barrier) & she was perfectly fine. I went to her lunch and sat next to her too and also leg touched, which she was comfortable with. I DIDN'T put my hand on her thigh though bc I don't want to go too far & make her uncomfortable. The lunch ended and I got up to leave for home. So I said bye to her & we hugged, except she hugged me SUPER tight. No female "friend" has been as aggressive with a hug like that before. So now I like her and she *should* like me.

-Problem:
I'm 18 & a freshman in college, she's 15 & a sophomore in HS. I'd obviously wait until her birthday in Feb. B4 I make a move (AOC is 16 in my state). So the age and life exp. gap is a problem, I found this out the hard way w/ my ex (15 & soph. me 17 & senior) how immaturity & expectations of teen girls can sabotage a relationship. I also have my own problems of hostility towards others (read my bio) that I need to work on as an adult. In addition, I plan on my next relationship being the last one (I like monogamy and marriage) but I know if I pursue it won't last more than 2 years. Lastly, college requires a lot of dedication & I'm supposed to date college girls. Should I try to date her or not?

Prologue: 21. Just moved to Manchester for first year of uni. Ex is 20, moved to Manchester for the same reason. See her everywhere (fuck my life). We were just beginning to talk about marriage.

New girl: Very sweet, quite shy but has a strong personality, very hot. We have texted a fair bit. Went to the Christmas market together etc etc Snapchat like crazy.

Problem: I like her. A lot. I am the kind of person who isn't too fussed about girls until 'that one' comes knocking and then I fall pretty hard. The issue is that I am still very messed up from splitting from my ex, I would have and still would die for her. I recently suffered from a case of The Very Shit Week syndrome (TVSWS for short) where everything was even worse than usual. I realized at this point that even though I am now pretty damn confident she likes me to some extent, should I even be in a relationship in this state? Is it fair to her or even myself for that matter?

I have left out many of the more gory details of the backstory, myself and the week just gone but hopefully it will be enough to get some decent answers.
Thank you very much for the people who managed to get right to the end and hopefully leave their thoughts on this situation. I will be happy to flesh out anything you see as relevant. Thank you :)