You have to look -beyond- the manga. If you just look at what happens in the manga, then not even MelloxNear makes sense. In the manga Mello hates Near's guts and all he wants is to be better then him and catch Kira. There's nothing even so much resembling "love" for Near. If anything, he's paired more with that stupid blonde lady who works for Near. *makes a face* Anyways, yeah, Near may have more patience when it comes to Mello, and he may desire for them to work together, but he generally doesn't seem to care for Mello in that way.
It's easier to pair Matt with Mello -because- he hasn't appeared in the manga more. Matt is -always- seen with or interacting with Mello, like a "loyal dog" as the game would put it. He seems completely devoted to Mello, and he even -dies- for him. I'm sure neither of them thought they'd make it out of their situation alive. Matt was willing to follow Mello to the end... if anything, he's the one character in the entire manga who really seems closest to Mello.