Where to start first, "it's not made clear how they are interdependent" did you not read hints. "blindly swinging a hammer"...Really? "blackmail Eric" It's not going to happen on it's on, you must stay up and catch Eric at 2:am, it want happen every night, the first time Alice must be topless, next time she must sleep naked(Eric will be inside the room). "I bought Alice the body suit" does not determine what path your on. And yes you are on war path with Eric, because you do not have "CONTROL" opportunity, and yes you can only have 20/21. That's not good or bad, just a fact. "pressing that skip button", yeah that's a lot of hard work. "My "Opportunities" screen shows I've done everything available" If you do not have the pictures of Eric, you could not possibly have done all that's available. The number at the top is not the number of completed opportunities, only the number found. "So I hope if I'm on the wrong path the game gives the chance to switch" Not after 2nd talk with Eric. If you don't want the war path, start a new game, or old save before that time.
Hints: I did read the hints. Here's an example of an unhelpful hint that doesn't describe how things are interdependent: for "Stick or carrot?" I'm told that I need to convince Lisa to take her shirt off while watching a film and the hint is "There's not much time. We have to make it before Lisa goes to bed..." But the path to this depends on the Schoolmate opportunity which is not mentioned. If you have not advanced that to a certain point there is no option to ask Lisa.
Similarly, at this point in the game the hint for "Party Girl" says I should try saying something nice and maybe Alice will act differently but advancing it depends on other events. I've already got all I can from saying something nice.
Blackmail Eric at 2am: An example of blindly swinging a hammer. A player must randomly stay up late in particular locations on specific days to trigger events. But not sleeping is punished by running out of energy. Perhaps I missed a hint that told me to do this? But since all my opportunities are listed under "completed" I am uncertain where to find this hint.
Thank you for telling me this is what I needed to do. Now I have done it and caught Eric. I see this is in the walkthrough as well. I try to use the walkthrough only when stuck. I missed this, so that's on me for not finding it. But it underlines my point that the game relies too much on chance (the walkthrough even says there's no guarantee you'll catch him, and it only happens on specific days.)
'"I bought Alice the body suit" does not determine what path your on': Out of curiosity, what does?
I have the "CONTROL" opportunity. But it does seem I'm on the war path, which is where I want to be. I definitely started by pretending to be on the friend path, with the intention of deceiving him. So I did not go to war immediately and the only thing I've done to cross him is buying Alice the body suit, after which he would no longer deal with me.
Skip button: It wastes a lot of time when the next playable event is a few days or a week of game time away. A simple control to say "go to X time" is something I've seen in other games. It's useful.
By "done everything available" I meant that the screen shows all under the heading of "Completed." I didn't express this as well as I could have.
Thank you for the parts of your response that were helpful.
Just a suggestion, take it or don't, but it's possible to be polite when responding, even when someone is wrong. You don't have to be snarky.