If you wrote if this way, I assume you could. This is just a response to the historical figures you listed, which were mostly "Don Juan"- types as far I could see? The "Don Juan-ity" would not work in Tolkien if you want the relationship shown in a positive light.Why can this not be true of a homosexual character? A person can fall in love and stay true to that person AND the person be the same sex or gender as them.
You can of course express what you wish to express. ;-) Still this one would not be a response to my point here. My point is still - if you want to show a queer relationship on a positive light in Tolkien it has to be free from promiscuity. So no "serial relationships". That's all I wanted to draw attention to.Can I just express, I dislike the implication expressed here that homosexuality is somehow unnatural or a corruption and wouldn't want that to be something that forms part of our worldbuilding, regardless of whether its possible to read this from the source material (which I don't think it is) or Tolkien's own opinions (which I don't see value for in this context).
(Still it would requires imho some very artfull writing not to make a queer relationship seem artificial in Tolkien's heroic world. Do not really see how one could gracefully pull this of without taking inspiration in Greek mythology).
The other issue, such an relationship, if faithful, would break the bloodline. Which automatically is bad in the context of royal houses - as we jave seen in Numenor and Gondor - a king/queen dying childless fastenst the decline of the nation. So imho best to choose someone whose bloodline is not important.