It's understandable to want distance if you can't be near a person whom you have feelings for but who only sees you as a friend. That is completely understandable and I totally and absolutely respect that, and you absolutely should take care of your heart, first and foremost.
But you can be an adult about it, have a calm conversation with the person, explain, and then take your distance until you are well and truly over them.

I have re-connected with more than one person over the years whom I had to break contact with for a good while (often years) either for their or for my sake, and one of them in particular is now one of my best friends in the whole world.

He recently flew from London to Vienna over the weekend, especially for my 30th Birthday. I love him with my whole heart, and he means more to me than a lot of people I had a "romantic" relationship with. And I know it's the same the other way around.

Interestingly, the fact that one of us was in unrequited love with the other at some point, and that we worked through it, with tears and pain, yes, but we worked through it, with conversations and then deciding to break contact for a while, until finally re-connecting about a year later, makes us more intimate friends than I am with a lot of other men.
I don't think we would have quite the friendship we have, if we hadn't had that history.
And this man is such a precious gift to me, I would not have wanted it any other way if I could, despite the uncomfortable and painful period we went through for a while.

It's all about the maturity whith which you both approach a situation like that.

But men who act jilted and betrayed and like entitled, pouting little children when a woman refuses to give them romantic affection but offers her friendship, and do not see the opportunity and gift she's offering by extending her friendship are victims of a society that teaches their boys wrong values in my opinion. Reacting with a temper tantrum when you don't get what you want is not only laughable and childish but a direct expression of a society in which it is acceptable behaviour for men to act like women owe them something, by reacting angry when they are refused something which they deem their right.
The truth is, it is NOT, and never will be, their right. And the sooner we start teaching our boys how to act like a man instead of a spoiled temper tantrum throwing brat, the better. For men and women.

Act like a man, not like a spoiled child, and I for one, will never forget that.
Even if you disappear for a while.

And if you want to reconnect after years of taking distance for your own piece of mind, I will be absolutely delighted to welcome you back into my life.

Act like a brat and a victim of misogynist bigotry, and I will also never forget...