It’s not like much changes. They’re not monogamous and Justin has another four months on his lease, so they’re not living together. They’re not married and Justin will never do Brian’s fucking laundry. They’re just the same as always, but now there’s a sense that they’re doing something, that they’ve got their shit sorted, and that’s enough of a change for now.
I love that ending... but it's not what you quoted. So I'm a bit lost...