Wow, I haven't been here in a while.
Anyway, I just wanted to say that while Saturn can be a devil, I find the hard
Neptune aspects much WORSE in a chart, and hard Uranus or Pluto ... essentially watch those big outer planets when they form hard aspects to your personal planets in composite!
Pluto = power struggles
Uranus = instability
Neptune = deception
But Neptune is the one I really look for precisely
because it's deceptive. Neptune squaring or opposing natal planets in a composite chart ... run like h*ll. Ha. I speak from experience. Conjunction can be a problem, but it depends. Neptune is the great deceiver. Everything can seem MAGICAL at first ... you've met your soul mate at last! And both people are inclined to participate in the deception, which isn't necessarily deliberate (although it can be). Sometimes one just projects onto the other what that one wants/needs to see. So while yes, a hard Neptune square
might mean intentional deception from the outset, not necessarily. Sometimes it can just mean delusions that may (perhaps will) eventually turn into real-world deceptions of things hidden, affairs, etc.
Saturn hard aspects, especially squares, can be worked with. Oppositions seem more (to me, IME) to be
external factors keeping people apart. Squares are felt more internally, but as a result, they can lend great STRENGTH to a relationship if met head on AND there are strong positives in the chart otherwise. They usually represent a
perceived limitation and or a critical approach. Without positive factors, that gets old FAST, and we often (again, IME) see or feel hard Saturn aspects relatively early-on, so we know they're there (unlike the hard Neptune). We can decide whether we want to live with them, or if there are enough goods to outweigh them. For instance, my mother used to tell me, when she'd give me frank critique, "I love you, so I'll always tell you when you have bad breath. You can count on it." As she
also always told me the good stuff and supported me, I learned to trust that the critique sprang from love and concern, not dislike or a need to belittle people.
With hard Saturn aspects, that's what we have to decide. Can we live with those limitations. Saturn is the teacher. Always. (Says the professor with Saturn on her ascendant, ha.) For some, Saturn can feel as if it cramps one's style. Saturn is the one who says, "No, you can't have a career as a singer because you're tone deaf."
But WHY Saturn says that matters. Maybe Saturn is just being mean. Telling the truth, but doing it to be mean. But maybe Saturn winces inside at the thought of someone Saturn loves getting up and making a fool of him/herself because Saturn doesn't want that person to be hurt.
So that's the puzzle one has to decide ... how does Saturn MEAN the critique/limitations, and can we live with it. In our natal charts, we have to learn to. But in composite (and synastry) charts, if we're not related to that person and required to stick around (*grin*), we can walk away.
But we'll usually KNOW it, going in. And Saturn will stick around, too, through thick and thin.
Neptune leads you down the primrose path straight to hell.
(Btw, my ex-husband and I had BOTH Saturn square Venus AND Neptune square Venus. The latter was far worse than the former. We also had some very good aspects, but not enough to make the marriage survive the double-whammy. Still, I'd go into another relationship with a Saturn/Venus hard aspect. I'll never again trust a Venus/Neptune, Moon/Neptune, Sun/Neptune, etc., hard aspect. Flee, flee, flee....)