I... what... no ...why
I had the same, thought but after thinking on it, I'm guessing Miya wasn't ready for a relationship. The fact that it was with someone older and with a girl might be too much pressure for a first relationship.
Honestly I kinda like the ending, sure it was bitter sweet, but not overly so and the reason for their break up made some since to me.
I would like to see a future comic with these two, getting back together or with others, either way it would be nice to see their next relationships work out.