Hey buddy,
I'm nobody to give tips, but.. hey, maybe I can help a bit.
You have 4 months. Take it as time for yourself. If you reread this whole thread from an outside perspective you would see it in a very very different way.
You're investing too much, you're wasting a lot of time overthinking, and you have a terrible oneitis.
Now you have 4 months. For what? To get to know yourself, to get over this oneitis, to flirt around(not cheating, just getting good with communication, seeing you actually have options, and seeing that there are great women out there), and improve as a man. Read, hit the gym, improve, study, work, do everything. Don't keep analyzing every little detail about everything.
I'm nobody to give opinions as I said, but.. I kinda went what you went through and got me nowhere, wasted my time for 8 months straight ONLY thinking about this kind of shit. It's very taxing to the mind and the body. And were am I left now? Dumped, didn't sleep with her, still thinking about her, heartbroken, and she's probably taking cock somewhere else in less than a week from the break-up.
If I just did what I believed, lived by my rules, didn't invest that much, and was just trying to invest in MYSELF and trying to live happy...damn, I dunno how would I be with her now, but I'd be a MUCH better man, much happier and wouldn't have wasted this much time in my progress in life.
Anyways, remember... You're more valuable than any girl you will ever meet. Work on yourself, get rid of that oneitis(even though you're gonna stay with her, this oneitis will only make you loose her ---> GET OVER THIS ONEITIS) and enjoy life.
Here's some motivation:
www.youtube.com/watch?v=VpXCz5dQHaY
PS: Check the blog of the user "hakuna"