Work Text:
Here's my theory on why Angel and Cordelia could have had a workable relationship, even with the happiness clause in effect. There's also some analysis about B/A and my problems with the relationship and the way Angel was portrayed in that relationship.
Why C/A had a possibility of working and B/A didn't.(In my view)
The people involved in C/A were mature adults. Cordelia knew exactly what she was getting into with her relationship with Angel, whereas Buffy was constantly caught by surprise by various revelations (vampire, happiness clause). Buffy, when B/A was happening was still very much dreaming of a normal life. Yes, she liked being a slayer more or less, but in her dreams Angel was normal, and she never quite accepted Angel as a vampire, she accepted him *despite* it. At that time she still thought she could have a normal life and didn't quite accept her role as a slayer (in my view).
Cordelia, by the time C/A was a possibility (Tomorrow), had given up wanting or waiting for a normal life. She had already given that up. She also had the luxury of getting to have a somewhat normal relationship with Groo, so she knew exactly what she was giving up if she got into a relationship with Angel. B/A was Buffy's first relationship so she didn't know what she would have given up for that relationship. Cordelia also accepted Angel fully, spicing his blood, making him actually be part of the world, instead of just hiding from it.
What's also different is Angel. He's a lot more complex when the C/A relationship is a possibility. I think many people love B/A so much because Angel is shown pretty much as the perfect boyfriend. He's not interested in other girls*, his jealousy is just right, it's there, but he's not a psycho, he doesn't pressure her in anyway, he's the one who has to be convinced of the relationship, he never complains about the amount of time they have together, Buffy's the one who instigates the sex, he still loves and adores her even after she sent him to hell, and he doesn't leave because he wants to, he leaves because he has to. It's not Buffy's fault he leaves, it's the circumstances.
As a supporting role, it's fine and dandy. But it's really, really 2 dimensional. When Angel is with Buffy he's nothing more than broody vampire with a soul and Buffy's boyfriend. He's defined by that boyfriend role. Of course the afterglow of making love with his girlfriend makes him loose his soul, it's the only thing he needs to be happy, because of his limited role.
*sidenote: he never said anything about not liking Cordy in Halloween, Buffy didn't get dressed up as Cordelia, she dressed up as an 18th C woman who worries about nothing but looking good. That's not Cordelia. She never asks about Cordelia, so he never says anything about her. She asks about Faith and gets an answer that he's not into bad girls, again, Cordelia is not a bad girl.
But then he gets his own show and he changes and matures and becomes 3 dimensional. He became the kind of character that needs more than making love to make him loose his soul. He gets friends, a family, a mission all his own. He's his own person with flaws and issues and needs. For the happiness clause to take effect he needs more. What that more is depends on his life situation. I think if C/A had happened during the baby!Connor arc or they had actually met during Tomorrow, his soul would have been in danger. Because during the baby arc, his life, for once, is good. He has a family, business is going great, add the woman he loves loving him back and it gets dangerous IF Angel let's his guard down. But considering the kind of guy Angel is, even if his life would always be the last scene of Provider, he has too many issues and flaws for it to be that simple. In the back of his head he would always be worrying about Angelus, or Connor's college fund, or whether he's a good father/friend/ boyfriend etc.
What I'm trying to say is that something exceptional has to be going on for the AtS-Angel to be simply perfectly happy. The baby arc and Tomorrow are dangerous areas to me because the overall happiness, the relative conflict freeness of those times might have made Angel slip momentarily. Any other time, I think there's just too much going on. Even if S4 had gone in a more happy C/A direction, I think the conflict with Connor and/or Wesley would have been enough to keep perfectness at bay. Same with S5, assuming she had been around I don't think she would have worked at W&H so there's conflict, plus Connor being gone would eliminate perfect happiness.
To sum up, as much as Angel loves Cordelia, he's too complicated and messed up a person to have a simple moment of perfect happiness.
How that relates to Buffy? Could B/A have worked with this complex Angel to who perfect happiness is a rarest rarity? I don't think so. To me, the reason B/A worked as long as it did was that Angel was a 2D character. All those things made him a perfect boyfriend but also made him very suggestible to easy perfect happiness because being with Buffy was all he needed, because that was his role. There's a reason Angel seems undeveloped when he crosses over. To acknowledge his development makes B/A less belivable. The guy who stood by his convictions against friends becomes the jealous ex. The guy who just went through 2 suicide attempts and is working hard to get his friends back, becomes the guy who goes to the funeral of a woman he met maybe half a dozen times, the last of which consisted of 'Leave my daughter alone', because he has to comfort his ex. The guy who sold his soul to the devil, slit his son's throat so he could give him up, who's best friend (and love) is in a coma became the 12 year old who complains about not being unique anymore.
When it comes down to it, I don't think B/A loved each other, I think they loved the ideas of one another. It's easy to love an idea, and Angel spent most of his time on BtVS as an idea, not a real person. For B/A with a complex Angel to work, Buffy would first have to get to know Angel the person, and see what she thinks about guy who's dorky, depressed a lot the time, with deadpan sense of humour, Manilow-loving, so old and so young at the same time, the guy who's both insecure and egotistical, the one who's willing to kill humans if he has to, the guy who forgives almost anyone, has a son and dozen other things that she has absolutely no idea about. Angel, too would need to get to know the more mature Buffy. Could they work? I guess it's possible, but nothing I saw in AtS made me belief it should.
ETA(27.8.2011): Because why would Angel get together with Buffy, who has no idea about his life and what he's been through rather than Cordelia who actually lived through all that stuff with him? That's one of the reason I can't really see Angel falling in love a third time, the person he'd fall for would have no idea about his life and I think that Angel really needs a person who's been through stuff with him. Okay, that was weird.