I'm not sure I'd have phrased it as "lies I've been telling myself", but I have a similar experience from a cross-cultural relationship, from mid 20s to early 50s. We had to work through conflicts more explicitly, with a lot more communication. Many things may be misunderstanding due to divergent assumptions, expectations, and even different body language signals.
I guess the "lie" exposed here is the way people can automatically believe they're seeing the truth of a social situation. It is easy to project false experience and motivation onto others. A more truthful approach recognizes windows of uncertainty around many encounters.
I think this applies to basic single-culture contexts too. Even in the same culture or the same family, we don't really know exactly what another person is experiencing.
Many seem cocksure that their social read is correct, and any grief is the other party's deliberate action. It takes a certain detachment to realize that your misreading of a situation may well be the genesis of a negative spiral, rather than a justified response...