The flashback to summer at the lake with Derek and Lynn (end of Episode 3) doesn't support the view that solo paths would be a disaster. Josy and Maya had known each other for a long time--plenty of time to get together if they were likely to fall deeply in love--yet Josey's plan was to move away from Maya and never see her again.
As for Maya, she didn't feel much sexual tension with Josy. When Josey kissed Maya for the first time in Maya's tent, Maya's reaction is shock. She asks, "What are you doing?"
This is just one example. There is plenty of evidence that Josy and Maya, like many young women who need to feel more secure in their lives at a particular time, are lovers by convenience.
Josy is clearly crushing on MC in a way that she never has with Maya. The fact that Maya at first comes across as a lesbian should be no surprise. After the way her father has treated her, a combination of deprivation of affection and strict control over her life, it's no wonder that she is afraid of intimacy with men when the VN starts. Her primary male role model was a source of fear and self-loathing. That does not mean she is not sexually attracted to men. Now that she's experienced a man who is caring (the MC), she appears to be learning that her primary attraction is to men, not women.
In short, Josy and Maya got we they needed out of their relationship while they were both going through a difficult time in their lives (stress of going or not going to college for Josy and Maya's family life). Moving on seems just as likely as any other outcome.