OT: Thanks CatParty, I wasn't expecting your post and laughed out loud and it scared my sleeping cat and he bit me.
I don't find it hard to believe at all that Barb may live for a longer time than assumed by other people.
When half of a long-term couple dies, sometimes the other is shortly to follow, but when Bob died, he hadn't been healthy for a while, which Barb had to know, either consciously or subconsciously, that he wasn't long for this world (maybe it started as far back as Bob's first coronary), so she "replaced" him with Chris, to buff the inevitable hurt of Bob dying. (Hell, I did that when we had a scare with my elderly dog and went out and adopted a kitten.) Chris, being Chris, doesn't have the know-how to really be his own person (even though he wants to,) so it created the perfect co-dependency for Barb to feed off of for years to come. Especially after the whole October incident, which she can also lord over him as an excuse that he MUST follow her rules or suffer further embarrassment.
Personally, I think she could go on for a long time; barring Chris doing something drastic and out of character, like packing up his shit, changing his number and moving out in the middle of the night, because she's still got that co-dependency of a "long-term couple" to keep her going.