Curiously it's somewhat the other way around for me, or I guess I've done a flip-flop realy, where I trended more slutty with Lena as development went but have turned back to the more wholesome version again recently. To me it's more the length of the game at this point.
I'm pretty confident you are not the only one, people come in all shapes and sizes and personalities after all.
Our histories reference the world we live in, even if the subject is otherworldly and foreign, yeah. I think there's a difference between recognising those connections and actively comparing the content you get involved with to people you know in real life. Not necessarily wrong or right, but I think people can vary somewhat in both what they put into and take from a story.
Some stories are about the bigger questions of life, sure, some are about basic survival too, it can very much depend on the circumstances and options people in a society have. Read inuit folklore for example and you'll find that most of their cultural narratives revolve around surviving in a frozen hellscape and explaining the things they see in the world, rather than bothering about moral questions in life, which tribal leaders were likely to deal with more directly in small isolated communities one might imagine.
Common trends sure, but not exclusive ones. There can be a certain culture to any combination of a given relationship and like your point about fiction narratives before, they also take and add variety to the narratives we tell about each other. Homosexual relationships have different tendensies from one culture to another depending on how accepted in general their family constitutions are for example.
In Northern European countries where homosexual relationships are generally accepted, you see the people in such families share traits with straight couples more often because the identity they represent is less controversial and therefore less isolated. When you are isolated from persecution or just pucling humiliation, the references material you can take and add to society is rather limited. So in a similar fashion to how an isolated community without a stable food source might build their mythology up around things other than moral questions, isolated relationships with no common ground with straight couples will also structure their dynamics in different ways.
I can't comment on the situations you encounter personally, but my point is mainly that there are structures of all kinds in all kinds of relationships and trends are influenced by the conditions in which they exist. Many homosexual relationships share certan traits with similar relationships because those are the sources they reference.
Anyway I think the topic of this thread of discussion is becoming more general than the scope of the thread, so don't be surprised if the mods come in a delete them

Suffice it to say that I think it's kind of you to try and not view your lesbian friends as objects of sexual interest, but Holly/Lena and Lena's other female options have sexual themes of their own that can be fun to explore and I don't think you have to feel an obligation not to explore them because you have friends that happen to share a sexuality with it. We are more than just what's between our legs and what we use those things for after all..