It was great, sharing an apartment with Georgia. He didn't think he could ever get tired of having her around. Still, there were irritations in living together that set him on edge. For one thing, his parents made no bones about the fact that they didn't approve. His mom in particular was forever dropping great clanging hints about marriage, respectability, and what the neighbours might think.
The reason that I mention this is that Phil told Elly a lie about how they actually didn't care about this in the least because it was a new age and besides, as a dude he was just supposed to get away with more anyway. The reason that this lie resonated with her is that she's sort of Hell-bent on seeing herself as being the victim of her childhood, never being allowed to be right or to keep up with what she sees a stupid, self-serving dicktard spoiled brat who stomps his feet and moans a grudging "Oh, all RIGHT!!!" when told to do the necessary as if behaving like a grown man is a big God-damned favor no one has the right to ask him.
This is perhaps why we never see Phil and his parents interact for about another six and a half years or so from now. You and I can well imagine Marian wringing her hands and getting all maudlin when she told Phil how much it hurt her to see baby boy living in sin; we can also imagine Jim giving Phil the "When I was your age, I had a real job and a family so what's your damage?" speech every chance he gets. The problem is that Elly can imagine neither thing and, when confronted with either Marian talking about how he's leading that poor girl on is like a dagger in her heart of Jim harrumphing about what Phil wants to be when he grows up, immediately forgets said event actually happened. She cannot allow herself to admit that Phil isn't the always beloved Golden Son who can do no wrong because doing so would mean that she wasn't treated like a servant maid living in a fucking dungeon. After all, if she doesn't have a childhood of unrelieved misery and heartache and unfairness to make up for, she can't very well justify owning her children's horses, can she?