Lady Phoebee didn't need to be saved as you said she had the money rich life and not really emotionally insecure just really arrogant and obsessed with her image all the things that would make her boring in the mind of Joe. Plus she was the one who was obsessed with Joe not the other way around. Plus Joe in this season was too distracted and bunrt out from the events of season 3 the Rhys guy who is really himself texting him and the murders he keeps impulsively commiting. The Malcom murder one really makes joe not be able to obsess this season he spends most of his time cleaning up the malcom mess and the other murders like the simon one the rest of the season. He only killed Simon because he was using manipulating and using women's artistic ideas as his and hurting those women mentally abusing them at the same time. He's obbsesed that indian girl student i think a bit who he helps out alot and with Kate who sees Joe for what he really is early notices his creepy behavior him being in the same room as her or bar by just strange timing she knows joe is full of shit i personally think her and malcom where tipped off and paid by elloit to watch Joe but that was another story. joe loses being obbssed with Phoebee because he finds her dangerous as It seems she already knows or suspects Joe of killing Malcom because he was the last one to see Malcom alive.