Based on what I know thus far,
kill Achro, fuck Carmen, marry Puzzle. I'll edit the why later ran out of time
Edit: So here the why's:
I know about Carmen the least and I couldn't justify either of the other 2 options for her, so fuck is my choice. It's a bonus that Carmen is female, afaik.
Even if the people I could choose from were different, as long as Achro is among them, I'd probably always kill Achro. I'm sorry Achro. I don't dislike you, in reality I feel empathy for you and your situation and would hope for your situation to improve, but if I absolutely have to kill someone, I'd probably always pick the one that has the least desire to actually live.
Puzzle remains and I guess I'll have to marry him. But honestly, I think, while his mental state doesn't seem to be perfect either, that our personalities would match rather well atm. I'm very competitive myself and seem to share a decent amount of traits and problems that accompany those traits with him, would help us get along for a longer period of time.
To explain one thing about the mental states and how they affect my choices, I don't think it's a good idea for someone with low energy like myself to be around depressed people too much, I'm very caring and have a lot of empathy, so depressed people, especially when I struggle to help them, drain all of my energy and turn me into a wreck. I need happy people around me to be healthy as a person. Maybe sounds self centred, but I'm 24 now and this is a lesson I learned from life, think about yourself first. You can't help your friends and the people you care about, if you don't function yourself, so there are times when I need to distance myself from other peoples problems and just focus on having fun and enjoying life, to recharge my energy, which I mostly do in solitude, as socializing also tends to drain a lot of energy when I'm already low on it.
SQ (3 users above, in this case Puzzle, Achro and myself)