Hi Andy
Wow - I read your other post (about using Wikipedia for research) and thought your book would be very interesting, but this puts it on my "must read" list - I love to read (and hear) stories about how people find true love - it humanizes those we don't know and makes us feel that we know them at least a little bit, and gives everyone hope for the future, so I definitely think you should include it in your book. The fact that earlier in your story you ponder the subject of love and relationships will make the tale of finding love so much more relevant and poignant.
I do think you should be open and honest about as much as possible - after all it's human nature for us to be curious, and that will be a very interesting part of your whole story, so we will want to know about it, but the best thing to do is use your own feelings as a guide (and of course those of your new love as well).....when the two of you read your words, do they make you feel like you've revealed too much personal detail? Anything that embarrasses you? Anything that you would NOT want your parents (or maybe children someday?) to read?
Only the two of you can decide what is too much exposure. Some people are comfortable with putting it all "out there" for all to see, even the not-so-pretty parts of life, others are much more private. You'll have to balance your comfort level with the bottom line of marketing 101 - if you want your book to sell, it needs to be interesting, and your love story will be of great interest to a wider audience than you'd imagine, especially the more it divulges. You will have to find the right balance of exposing enough to generate interest vs. going so far as to make either of you uncomfortable.
Of course if you want anyone to read a few passages for you and give you feedback, I'm your gal! 
