Do you swap the Pleasant twins boyfriends?

Hi :)
They never seem to want each other when in University. :)

I usually leave it up to them. Most of the time when I get the four of them together, Lilith will autonomously flirt with Dustin and cause drama. If that happens I have both couples argue and break up and look for comfort with the other victim. This has happened quite a bit in my Sims 2 games, usually when all four are at the Pleasant house visiting or in the dorm at college.

Don't much care about Dirk x Lilith, she can just as well be with Alexander Goth (there is a brief window when they are teens together).

I like Angela with Dustin, because they have two big similarities:
- Their love for nature
Angela's bios mentions she wants to work on a fish trawler. Now childhood dream jobs come and go, but she will always retain a love for the sea, sailing and fishing. Meanwhile Dustin's One True Hobby is Nature, that includes fishing. Ta-daa, many happy picnic dates at the local park!
- Their devotion to their family
Dustin carrys the whole household on his back with his job, while Brandi scolds him for his "bad" grades in a scripted scene (he is a solid C student, though). It is also implied in his memories that he fought Gordon King ones, most likely to fend the burglar off. Now Dustin has to work for Gordon to ensure he leaves the trailer (and within the mementos of Skip) alone.
On the same leaf Angela puts on a facade for the outside world, keeping up pretentions that everything is well in her family. Not just that, she tries to be the perfect daughter.

Currently I play with a megahood so they end up with anyone. Angela married Alexander Goth and Lilith is single. Dirk is also single and and Dusti is married to Jill Smith.

I always keep Dustin & Angela together because I think they make a good couple, but I usually break Dirk & Lilith up because I never thought they were a good match plus I always marry Brandi & Darren. That means Angela & Lilith would be invited to family gatherings,etc. and I don’t want all that drama. The constant fighting gets on my nerves.

I always thought that it would make more sense for them to swap, but I've never actually done it

I like to keep them together although I let them do what they want when they age up to (young) adults.
I feel like Dirk brings out the good in Lilith and both of them bonded over the difficult things they were going through in their lives. Every time I play with them, Lilith moves in with the Dreamer family while still a teen. Even if she and Dirk don't stay together through university, they still remain friends and I find them to be so sweet together either way. In one of my games Lilith ended up with Johnny Smith and Ophelia Specter, and Dirk was best friends with all three of them. Eventually I just moved him in and he helped take care of their kids.
As for Angela, I agree that she's putting on a facade but because of the pressure by her parents who are trying to put her on a pedestal and make her this perfect ideal daughter, and so she's dating Dustin as a way of acting out against them. They rarely stay together in my game, Angela usually breaks up with him when she goes to uni and either finds someone else or stays single. In the same Pleasantview-Strangetown game as before she ended up with Tank Grunt, which I feel is kind of perfect because they both know what it's like to be pressured by their parents to be a certain way.

In my current save, adult Dirk finally got the want to flirt with adult Lilith and she rejected him, they have no chemistry at all...

TBH, what I think of this is... Sims 2 neighborhoods tend to be small and not have a huge variety of people, thus most players end up keeping them together because they were officialy together at the beginning of the game or swap their boyfriends to keep the drama going harder than before. Honestly, maybe the could swap boyfriends irl to piss eachother off but then that would highlight that maybe they didn't actually love them before and realistically its SO unlikely for someone to be married to their teenagehood crush/boyfriend/girlfriend. I don't think both couples would stay together, irl, maybe one of them but not both. Angela and Dirk, Angela and Dustin, Lilith and Dirk or Lilith and Dustin. IDK. Maybe Lilith and Dirk, as some pointed that their relationship seem more genuine while Angela seems to be usin Dustin to piss her parents to stop placing her on the "perfect little girl" stereotype. IDK. haha

I go a step further. I get Dirk and Dustin together, they're made for eachother, even if its solely because of the potential of saying they're the Double D couple. Also because it drives drama even further than the limits.

To elaborate further, just like the L/D and A/D mix both have a deceased parent, both are either a problemchild or a do-gooder and on both spectrums of poverty. They're perfect at being standins for either Pleasant.

It just works.