So, when it comes to one-sided Ford squared, most of the time it's on Fiddleford's part
But guys, what if Ford was the one head-over-heels in love with his roommate???
And Fiddleford doesn't reciprocate not because he's straight, but because he doesn't want to be grounded into a committed, official relationship. So Ford is respectful of that and after they graduate he still really misses Fiddleford.
Later Stanford invites him over to live with him in Gravity Falls, and Fiddleford actually considers being with Ford, but then he has a really horrific run-in with Bill Cipher!Ford, thwarting any romantic feelings budding in Fiddleford, because he can't live with that. That's right, Bill manages to mess up everything. Again.
Even Post-Weirdmageddon Fiddleford is reluctant to jump into a relationship due to a) insecurities and b) he wants to work things out first in order to maintain a healthy relationship. From there it's the happy ending, where Fiddleford and Stanford, though it took a long time, realise that they were meant to be together. Or you have the Fiddauthor angst(tm) where Ford is hopelessly in love the rest of his life. They manage to retain their close platonic friendship though.