I think the question at the front end of this thread is a great one:
why love Boromir?
I think that in searching for an answer to this question most people turn to what makes him admirable and great -- and there are many things here (see above -- wow, but you guys dig on Boromir!
). What makes it 'possible' to love him, though, are his flaws -- or, rather, his flaw, which is the desire for personal glory and reknown (cf The Council of Elrond where he keeps interrupting people who know a lot more and lot better than him).
Eowyn found out to her great sadness and pain that loving someone above the human norm is a dangerous and painful thing. Aragorn is not for 'real' people to love, but to cherish and follow -- how could there be anything like a happy marriage between Aragorn and a mere normal mortal? I love Aragorn so much that to be in his presence daily would render me mute and abject with worship: not a healthy relationship.
Boromir is closer to our own level; his flaws are our flaws. Those who judge him for succumbing to the temptation of the Ring don't really ask themselves how they would have done in the same circumstance. . .
I love him not in spite of his attempt to take the Ring but
because of it. It shows that he's someone I can have an equal relationship with: flawed mortal to flawed mortal.