Man the art is really making me think of the original Sailor Moon anime, and a bit of Ranma, it has that 80s-90s quality to it that a lot of modern anime lack.
I don't mind the ending. It's the world we live in, if we jump into the first relationship option that presents itself, odds are it won't work out. Shrugs It's life, especially when you're new to dating. It takes a bit of experience to get to the point where you can weed out unsuitable partners quickly. Some people are lucky and run into their soulmate right away, the rest of us have to go through an awkward dating phase.