I definitely felt that way about Sam. Poor Sam! He deserved so much more! It was very, very clear that Kara never loved him the way she should have if she was going to be involved with him.

But I don't see it that clearly with Athena. Actually, I think maybe that's why I was drawn to the two of them: I like the sort of gender inversion thing where the man is the one who is really in touch with his emotions and the woman is less forthcoming (see: Spike and Buffy, Logan and Veronica, etc.). So yeah, Helo is certainly just like brimming over with love for her, but I don't see an absence of love (the way I do with Kara, who was never more than fond of Sam), but more that she doesn't communicate it as clearly.

Though that's obviously open to interpretation.