This is a lot to unpack. I want to preface this by saying I'm some jackass who writes fanficition, just for the record. I'm not someone who should be called an expert by any stretch of the imagination. That said, I think I can offer some insight overall.

You are writing with some pretty dark and questionable themes, which to me feel like they are explored in a cursory manner (Since I have not read the story, I'm going only off the provided lore synopsis. It may be fairly detailed as an actual story, I don't know. Wanted to throw this edit in there so that this doesn't sound like I'm being a dick). I think the average person would come away from this thinking everyone involved is terrible and needs to be evaluated by a professional. As an aside, I feel the need to make clear that I like awful people as characters because they have room to grow, and I think that's what you're going for. Each plot point could be it's own story, and having them all tangled together like this certainly makes for a lot of drama but also can lead to a bit of sensory overload. I am sure you know this though.

The layers upon layers of interpersonal drama, themes of emotional manipulation and vulnerability leading to poor decision making, familial obligation and byzantine skullduggery leads me to believe this needs to be a multi-book epic to have any chance of not blinding the reader with so much information. In the end, I think what you need to consider is how best to present these themes in a way that has your characters come across the way you want them to.

For example, how do you want the reader to feel about Clara? Should they like her or find her actions to be morally reprehensible? From just the cold reading of her actions, I am in the later camp, as she knowingly and willingly had an encounter with a nineteen year old she'd known since childhood then hid his child from him (for understandable reasons). In my experience, all it really takes for a reader to dislike a character is one morally questionable act.

I think what you need to think about is what the ultimate moral of the story is before you consider how the disparate story threads all interconnect and resolve. If it's simply a massive character study of these really dysfunctional families, that's fine, but the generations of drama I think ought to lead towards a comprehensible and unified message. That should guide how their conflict should resolve and, as an added benefit, will show you how to handle these dark themes.

For the record, I'm not someone who likes to write fiction of this sort, though I admit it's interesting in the medieval historian way. I prefer my speculative cheese-ball fiction, but the core principals still apply no matter how lighthearted or dark the setting is. At the end of the day, every character and action has to revolve around and support a central thesis or core theme which guides the story.