Been playing this game by Johnny Reb all day and failing hard... There's a walkthrough on Delron, but it seems to be failed or incomplete, doesn't it? Either that or the ending is very disappointing...

Anyhow, if anyone has a walkthrough, I'd be gratful. Tried google and everything, but either I suck at it or there's just not that many of them.

Where can I find this game?

I've never completed The Birthday, but the walkthrough you're referring to is the only one I could find.

There are also a handful of references to the game if you search old aifarchive posts, one of which suggests that there might not be sex in the ending:
"you don't actually get to have sex with her in this game but this is the best ending you get"

If you want a more informed opinion than mine you'd be best off posting on aifgames.com or the aifarchive Yahoo group.

Thanks. Was wondering if maybe the game was incomplete or something...

Hard to imagine that being the ending. Technically the game has no sex.