“kanashii” means sad. So the sentence literally means “I’m sad.”
Judging from “ne”, it is probably said when asked about his or her impression.
I think that the sentence means that “I’m disappointed,” which depends on the context, though.
I am sad.
This is somewhat formal, and is not how to talk among friends. The gender of the speaker is not known, but the formality of the conversation is clear.
it’s imposable to assume which of man/woman is talking.
It means “I’m sad, aren’t I.”
“i am sad…” (probably a girl talk)
i like you so you like me?