A Question to End All Questions

How do I tell someone I don't love them without breaking their heart?

I was asked this question by someone that I've grown rather close to over the past month, and it's a hard question. Though, while it's a hard question, the answer can be any variant of easy and hard. Though, the polls seem to reverse with the less amount of heartbreak you want to inflict. See, the less you want to break a heart, the more liable you are to accepting requests or favors to make up for it, and that can lead to some hurtful situations.

Now, the best advice I can give is to match the other person's personality.
Wait, what?
Yeah. You read right. If the person you want to tell is timid, be timid with them about the news. If the person is brash, be brash with the news. People don't necessarily mind as much when you copy the way they are.

Now, if you're wise, you would disregard the previous advice.
((Wait, what?))
Be gentle, but firm. Tell them - in your own words - that you'd rather not keep your status as close as it was. That you need a little distance, maybe a little time.
Now, if the person reacts in any form of anger, stand your ground and - well, be afraid - but try not to show it.
If things go well and the person reacts like it doesn't bother him/her... it does. They're just bottling it up around the news-bearer and the recently broken-away - and it hurts worse when they're both the same person.
If the person reacts with a flash of a smile, or an all-out smile, they're taken by surprise and confused as to if you mean what you just said.

With all of these responses, you have to make sure that they have ample room to ask questions and get to know why you're doing it. If you can't explain exactly, just try to give them a somewhat reasonable over-look, without going into too much detail.

If the person gets violent, then get yourself away from them as quick as possible. Keep collected, but not calm. You don't need to be calmly walking away from someone who wants to stab you in the back. Give them room to adjust and time to think.

If the person reacts with understanding, it's often a sign of confused generosity and they're just letting you do what you need to do so that maybe through seeing what you do, they can understand the situation better.

I would like to say more on the matter, but I'm no expert, and the only experience I have is through what family members have gone through.

Good luck.

((Insert Incomprehensible Babbling Here)) - Projected "Disembodied" Voice