None of your relationships took the standard shape
Nothing about how you have partnered with anybody has followed the usual template. Saturn in Aquarius in the 7th house means a close relationship has to be designed rather than entered, and the design work is genuine rather than an affectation.
The 7th house is the arena of one other person with an equal claim; Aquarius will not adopt an arrangement simply because it is the customary one. Saturn insists that whatever you settle on be workable and honoured. So your partnerships are unconventional, thought about at length, and considerably more explicit than most people's.
The fear is being absorbed into a couple
What worries you is not the person but the institution: the shared identity, the assumption that you now think and want the same things, the slow disappearance of the individual into the pair. It is a real risk and you overestimate it, which is why you have kept a distance in relationships that were not actually threatening anything.
It comes due when the arrangement has to look ordinary
The test is a situation where the conventional form is required for practical reasons: a legal arrangement, a family occasion, an institution that recognises only the standard version. Complying with the form while keeping the substance yours is available and it feels like a defeat. It is not one, and the distinction is worth holding onto.
Write the bespoke arrangement down somewhere
Because your arrangements are custom-built, none of the default assumptions apply, which means anything left unstated is genuinely undefined rather than merely unmentioned. Putting what the two of you have settled into writing — not as a contract, simply as a record — heads off an entire category of disagreement that conventional couples are never exposed to in the first place.
A partnership designed rather than assumed
What this builds is a relationship that actually fits the two people in it, arrived at by discussion rather than inherited from a template that suited neither of you. That is rare and it required the difficult conversations at the beginning. It is worth noticing that the conversations were the reason it works, since they were also the part that nearly ended it.
You need a partner who has their own life running
Somebody whose interests, friendships and occupations are genuinely their own is not a compromise for you, it is a requirement, and a partner who wants the two of you to be a single unit will not survive the arrangement. Say so early and plainly. It sounds cold and it is the most useful sentence available in the first month.
Working partnerships need the roles written down
You will design a genuinely fair collaboration and then leave the specifics undefined, on the assumption that reasonable people work it out. Reasonable people work it out for about eighteen months. Putting the division of authority in writing at the start is not distrust; it is the same design instinct applied one step further than you usually take it.
Independence and intimacy are not actually opposed
You have been operating on an assumption that the two trade off against each other, so every deepening has felt like a loss of something. Plenty of evidence in your own life contradicts it. Watch what happens to your autonomy during a good stretch in a relationship, since the observation tends to be the opposite of the theory.
Separate finances by design rather than by default
How money works between you was worked out deliberately rather than drifted into, and it probably does not resemble what either family did. That is a real advantage. The one thing bespoke arrangements need and standard ones get free is a review date, since nothing about your version updates itself when circumstances change.
Both families have opinions about the arrangement
An unconventional partnership attracts commentary from relatives on both sides, usually indirect, usually persistent, and usually delivered as a question rather than a statement. You have generally responded by explaining the reasoning, which reliably invites a further round of discussion. Declining to justify the arrangement at all is a perfectly legitimate position and it ends the conversation considerably faster than reasoning ever has.