Dear Carolyn: This is so wrenching to say, but I'm going to have to break up with my fiancee, and I'm trying to figure out the least painful way to do it. We've been together four years, and we decided to try for a baby. It turns out she is infertile. We're both devastated by the news, but I know it's worse for her.

She's already suggesting adoption or a surrogate. I told her we could talk about it later, but the truth is, I don't want that at all. I want to have my own kids, in the usual way. I guess that sounds selfish but it's how I feel, and I can't change it.

I know that means I have to break up with her even though I love her. There's no way I can put her through a breakup right now, when we're both so raw and vulnerable, but is it worse to string her along knowing I will eventually have to do it? What's the kindest way to proceed here?

— Leaving

Leaving: Dear goddess. There isn’t one. There’s just marginally less unkind.

Plus, not everyone would want the same thing in this situation. Some people would be furious at a breakup right now, and others would be furious if you postponed it.

Some, too, would be furious regardless, because the fury is inevitable and its having to go somewhere means it will find whichever vessel you set out for it.

So stop. Say nothing. Think.

The next brood mare person you date may not be able to conceive, either. Or you may conceive . . . and (perish the thought, sincerely) suffer miscarriage(s) or stillbirth(s). Are you going to leave again?

Or, what if you make healthy babies, but you wake up one day to realize you married a uterus and failed to prioritize good conversation?

I actually do have some sliver of a degree of sympathy for wanting the life you want. I type it here all the time, that couples who disagree over kids have to sacrifice either their family preference or their relationship. It’s not a have-it-all kind of situation, and we have to be pragmatic about who we are.

But it’s also not (anything close to) a perfect world, and we can’t reasonably treat our preferences as some kind of cosmic grocery list. You don’t choose a breeding pair, you choose a quality life partner — because everything beyond that is subject to the whims of fate. Kids, number of kids, health of kids, survival of kids — all YMMV. Even the charm of your partner’s qualities can be of variable endurance, so projecting wisely is really all you’ve got.

So ask yourself: Which is more important to you, the quality of your partnership or the results of it; and, would you like it if someone chose you for sperm access?

Don’t stall forever, just till the shock passes.

None of this is to argue for staying with your fiancee. If you can even be thinking breakup, then either she’s not the right person for you or you’re not mature enough to tell whether she is, which is same-same at this point, for all practical purposes. I’m just saying the whole pick-the-girl-for-the-fertility idea is due for a rock-hard rethink.

Write to Carolyn Hax at tellme@washpost.com. Get her column delivered to your inbox each morning at wapo.st/haxpost.