I don't know about the confessions in my own writings. It depends on the story and how it's given of course.
For one of the story I'm working on, I think when the characters get to start and enjoy their relationship are the 'highs'. Which is just like, right place, right time. Can't really enjoy love when there's other things going on. I don't think... ..I mean, yeah, it depends on the story.
In my current work, the confessions aren't really like, confessions. It's just obvious by that point since interactions are like micro confessions build ups overtime. When the confessions happens, it's just more for like clarity and comical aspects. That there's no more flirtatious charade. But the feelings between characters and what is portrayed to the audience, should be clear by then, is my aim.
I think when the characters finally handle their responsibilities and can actually spend a day together doing whatever. Without having to constantly think about what they need to do next to not mess up and upkeep their personal lives, are the 'highs'.
I suppose to simply put, when the characters in the relationships are both happy with things, those are the high points for my writings.
When there's too much going on, they can flirt and stuff, but like. That's momentary and brief, they have to constantly return to their responsibilities and what they need to do. So it's not the same as being able to totally focus on themselves and their relationship, that's a luxury in ways. When they finally get to, make sense it feels like the 'high'.
I like to write romantic relationships that formulate from established friendships first. So in ways, their 'relationships' started long time ago, the romance is just continuous new aspects of it. Those high fives and best friends vibe still exist and have existed for a long time.