There's three Lannisters left and one isn't even on their side (Tyrion). Their patriarch is dead, killed by his own son. They've done a hell of a job benefitting from others' schemings in this show, and sometimes just flat out luck and poor decisions by opponents (hey, let's bring a wight to Cersei, who won't change her mind anyway, and lose a dragon in the process!); let's not pretend they haven't.
Tywin - Murdered by his own son that he hated.
Tyrion - The only sensible one in the bunch but still stupid enough to think he can win his psycho sister over.
Jamie - Fucked up his alleged redemption arc because he wants to **** his sister.
Cersei - Drives everyone who loves her away including the brother she is fucking and her own son who would rather murder himself rather than have her as a mother.
Joffery - Piece of shit product of incest that was so disliked that people celebrated when he died horribly.
Myrcella - Mother is so hated that the place she thinks of as home ends up poisoning her.
Tommen - Good lad so despises the horror that is his mother that as noted above he happily murders himself rather than continue on as a Lannister.
Unborn Lannister Baby - Will mercifully be spared growing up in this terrible piece of shit family when Cersei hopefully dies. The irony is by virtue of not being born and raised in this family, immediately becomes the best Lannister of the bunch by default.
In short, pretty sad when your never to be born child represents the best your family has to offer.
