Nobody warns you because it's inconvenient to the narrative we sell about love and sacrifice. We want it to be simple: they love each other, one person moves, cut to the part where they're happy. The messy middle - where you're lonely and guilty about being lonely and subtly angry and also committed to the relationship - doesn't fit in a greeting card.
I've been on both sides of this. I moved for someone once and it went badly. I was resentful, he felt guilty, we basically imploded. Later, my current partner and I made a different choice: we both moved to a third city. Financially stupid, logistically complicated, but it meant neither of us was the person who sacrificed. It changed everything about how we navigated the transition.
Here's what I'd say to anyone considering a move for love: that choice is legitimate, but name it clearly. Don't call it a joint decision if it's not. Don't pretend it won't cost you something. And critically, understand that your partner can't be your entire social life now - that's too much pressure on them. You both need actual community, not just a couple bubble.
Your loneliness isn't shameful. It's not selfish. It's the actual, real consequence of the choice. And if we're going to keep asking people to make these moves, we should at least be honest that it's a sacrifice, not just a romantic plot point. That honesty might actually help people decide more wisely before they do it.