Wonder Woman sure hangs out with that Steve Trevor guy a lot. It makes sense, what with him having been literally the first man she ever saw. On the other hand, Wonder Woman has been around for close to 80 years now, and she and Steve were only an item for a few of them, so what else has she been up to in all that time?
We all know about Melrose Place: DC Edition, otherwise known as New 52, in which Wonder Woman dated both Batman and Superman just to figure out that both of them were kind of the worst. However, she's had some loves who rate even stranger than an alien and a guy who dresses up like a bat to intimidate people. Settle in, because this is going to get a little weird.
Kasia / Mala
Kasia and Mala aren't the same character, but there's no real difference between them and they serve the same exact function in Diana's life, so they're going to share an entry. Mala made her first appearances in the early days of Wonder Woman when Diana was out there on the front lines, fighting delusional debutantes dressed up like cheetahs and tying people up left and right for THE TRUTH (and maybe other, sexier reasons also). Mala was around when Diana first discovered Steve Trevor on the beaches of Paradise Island, and right away, she was not even one little bit interested. Diana may have been intrigued, but Mala was like, “Return to sender!” while trying to push him back into the ocean.
Kasia, on the other hand, made her first appearance in the recent Rucka relaunch of Wonder Woman, but played the same role as Mala. She also doesn't trust Steve and doesn't want Diana to leave the island, noting that it “would break my heart.” Diana is like, “noted,” but then just bounces anyway.
While Kasia was portrayed as being somewhat more reasonable and open-minded than Mala, they had more than a few common traits between them including: a severe distrust of men, complete bafflement at Diana's interest in the outside world, and at different times heavily implied to be romantically involved with Diana, who then leaves them to hang out with Steve Trevor and live it up in “the world of men,” after which time we don't really hear too much from either Kasia or Mala again, because Diana is 1) as cold as ice, and 2) willing to sacrifice their love. The best thing for both of them would be to forget about Diana by dating... any of the other hundreds of women on Paradise Island, I guess. On the other hand, jeez, Diana! These two completely interchangeable characters really loved you!
Ronno the Merboy
If there's one thing I know as a truth, it's that not many DC characters made it out of the Silver Age without dating a merperson. It's The Shape of Water all day every day in '60s-era DC comics. We are talking about a group of characters that took the term “dating pool” incredibly literally. You might wonder why everyone back then was so interested in dating merpeople. (For the same reason everyone today wants to date merpeople, too.) I didn't make the world, I'm just living in it, and the truth is it's a basic commonality that we all want to date fish-human hybrids. It's an indisputable fact of life. Ask anyone on the street and chances are they have already decided in their hearts that they would definitely hook up with a merperson if the opportunity arose, and Princess Diana of Themyscira is no different.
Ronno helped DC uphold that proud tradition of its superheroes treating Atlantis as their Vegas by showing up to flirt with Wonder Woman back when they were both teens. It's good that people are predetermined to want to kiss fish people, because Ronno's one-liners were anything but smooth. At one point, he refers to teen Diana as “the prettiest fish” he's ever seen, which yikes. Still, somehow, against all logic, common sense, and even the laws of basic anatomy, they did have a brief fling in the comics, which would have actually been kind of cute, if he wasn't half-fish.
Although once just a Merboy, Ronno grew up to become a Merman and started calling himself Manno, because this guy had one hell of a complex. Diana was still pretty complacent towards him as a love interest, which is likely for the best because he was completely erased from existence in Crisis on Infinite Earths, never to return, unless someone decides to Alan Moore Ronno and bring him back as a brooding shadow of his former self. Personally, I think it's okay if we just leave Ronno be and call it a day.
Wow. Io is...something else. More like “I-oh my god what a babe.” While not the best characterized DC hero, Io is a weaponsmith on Paradise Island, so there's a lot of shots of her lifting heavy things and hitting stuff with hammers and wiping sweat from her brow. While Io might not be a perfect match for Diana, she is still yet an incredible babe, and her love for the princess is profound and true.
Even in her first appearances, it's obvious that Io has a pretty heavy crush on Diana and has made it clear that she's willing to lay her life on the line for the princess. That makes her the kind of ride-or-die Diana casually shrugs off pretty consistently in her life, so, again, Io's chances might not be great.
On the other hand, hopefully Io can take comfort in the fact that she lives on an entire island of women that are probably in love with her despite the fact that she's not the Io of Greek mythology and thus can't turn into a cow or anything really awesome like that. Weaponsmith is a pretty good back up career.
One thing is pretty consistent with Diana, and that's her love for both men and women with blonde hair who disagree with her constantly about almost every decision she makes but then are forced to go along with it anyway. Nemesis mostly appeared in the Gail Simone run of Wonder Woman, and while he bore more than a passing physical resemblance to Steve Trevor, he was... actually really a lot like Steve Trevor personality-wise as well. What can I say? Girl has a type.
The two characters had a flirtatious and mostly endearing back-and-forth for several issues, and they were even kind of a thing for a minute. Diana brought him home to meet her mother and he was inducted into the society of Amazons, despite being not an Amazon.
All mediocre things must come to an end, though, and Diana ultimately revealed that she wasn't truly in love with him even though she was down to be impregnated by him and live a life together. Girl! Mala, Kasia, and Io are waiting for you! You don't have to settle! Anyway, because Nemesis isn't a chump, he wasn't at all down with living a full life with someone that only sort of liked him, so he broke things off. Diana, to her credit, got over it pretty quick.
Introduced in Phil Jimenez's underrated run, Trevor Barnes was introduced more or less as “not Steve Trevor.” Not only was his appearance ever-so-slightly different, but he was a soft-spoken diplomat, unlike Steve who was loud and always tripping over things.
Diana obviously had a crush on Trevor even in the beginning, but he turned her down for a date, claiming that she was too far out of his league. This guy! Even when he's turning you down, he makes you like him all the more. The chemistry between them finally became too tempting, and they did go on a few dates, temporarily becoming an item before Jimenez left the book and Barnes was rapidly killed in the storyline immediately afterwards. Honestly, it was uncalled for. Trevor deserved to be happy, DC!
Still, Trevor really stood out among Diana's many loves, mostly because he was a really chill guy who you could imagine spending most of his nights at home with a book and a glass of wine. Although his role in Diana's life was brief, it could have been more, although in the end, personality-wise, he might have been a better match for Diana Prince than Wonder Woman.