If you seriously think that a couple that live together don't spend together the lion share of their free time just because they don't text enough about the time they are actually spending together then I don't think there is any actual hope for you.
We see in the game that: they live together, they spend time together and with their friends, when they aren't together (because MC is working, or Laura is visiting her folks) they text and sext all the fucking time, but for some reason we're supposed to believe Laura spends more time with Nathan?
You clearly don't understand subtext if you need everything spelled out for you.
Let's see the last update: Laura proposes to invite Nathan over, if you accept you get to see the scene. If you don't, it's obvious they spend time together alone, but the chapter ends without showing anything. What do you think happens if you choose to not invite Nathan over?
What do you think happened all the times when Laura texts MC "how are you today?" and he replies "tired from last night"? Did they go for a midnight run?
Are you for real?