Two things at once: deep loyalty and a wandering attention
Uranus travelled through Gemini in the mid-1940s and again from the mid-2020s, so the restless mental wiring is common property with a whole span of birth years; the seventh house is the half decided by your birth hour, and yours put it squarely into partnership.
The result is a person who is genuinely committed and permanently curious, and those two do not cancel out. You can be entirely devoted to somebody and still find another mind fascinating on a Tuesday. Managing that honestly rather than pretending it does not happen is most of the work here.
Read as uncommitted, running on interest
Partners conclude you are half out of the door because your attention visibly moves. What is actually happening is that attention and commitment are separate systems in you, and only one of them wanders. Saying that explicitly — that interest is not the measure of loyalty here — spares a great deal of unnecessary anxiety on the other side.
The interest turns over without an announcement
What you want from a relationship can change substantially and without warning: the terms, the amount of contact, what you are looking for from it. The change is internal and complete before anybody hears about it. Mentioning a shift while it is happening, even vaguely, is what stops a partner from experiencing it as a sudden reversal.
You can talk a relationship back to life
Where most partnerships die of silence, yours can be revived by conversation, and you are unusually good at finding the question that opens something up again. That is a genuine skill and it works on friendships and working relationships as well. Using it early, before the silence has set, is considerably more effective than deploying it as a rescue.
A partnership of two separate people
What builds here, when it goes well, is a relationship where both parties remain distinctly themselves and interested in each other's separate lives, rather than merging into a single unit. That is unfashionable and durable. Protecting the separateness deliberately, particularly during the periods when merging would be easier, is what keeps the thing that made it work.
You need to be argued with, not agreed with
A partner who concedes every point will lose you without either of you being able to say when it happened, because agreement gives you nothing to think against. What you are actually asking for is resistance from somebody who has considered the matter. Saying that plainly is important, since from the other side it looks exactly like being told you enjoy conflict, which is not the same thing at all.
Your friendships and your partnership overlap
You do not keep a separate social world; partners get absorbed into your friendships and friends become part of the relationship, which is warm and leaves nowhere to go when something is wrong. There is no neutral ground. Keeping one friendship entirely outside the partnership is worth the small effort, and it will matter enormously at some point.
You need somebody to think alongside
The central requirement in your life is not company but a mind to work things out with, and you have been unhappy in every arrangement that failed to provide one however good it was otherwise. That is a genuine specification rather than a preference. Treating it as the first criterion, rather than something to hope for, changes how you assess a promising person.
You negotiate better for somebody else
Acting on behalf of a colleague or a client you are direct, unembarrassed and effective; acting for yourself you soften everything and settle early. It is the same skill and it stops working the moment you are the subject. Writing down what you would advise if this were somebody else's situation, before the conversation, is a crude device and it recovers most of the difference.
You explain the relatives to each other
Between your family and your partner's, you end up doing the translating: putting one lot into terms the other can accept, smoothing what would otherwise be a permanent misunderstanding. Nobody knows you are doing it. Stopping for one occasion, and letting them meet each other unmediated, tells you how much of the work was actually necessary.