You notice small faults, things that just irk you for no good reason. But you'll look past them because the love is worth it. Working on that love become actual work. You start to resent it, wonder if you made the right choice. You can't help but notice the other options out there but, because of your code of honor, stay true. You made a comitment. A COMITTMENT! You weren't wrong, you just need to get past this rough patch and everything will be fine again. If only you could rediscover the spark again, remember how it exciting it used to be. But that other option is so intriguing. Perhaps it wouldn't hurt if you just flirted with the idea a little bit...
This has happened to me at the end of every work in progress. Each time I have had to force myself to stay true, to not stray from the path. In the immortal words of Pat Benetar,
Don't want to leave you really
I've invested too much time
To give you up that easy
To the doubts that complicate [my] mind.
Sigh. I will finish this book