Wow, I think this idea is amazing. Well done for

The distance
to your heart
is further than
a cross-country trek.

- you opened this with showing that this person keeps you at a distance for whatever reason and that you struggle to get there because they keep you so far away.

The way is unpaved
and treacherous-
never mind the obstacles that
you will place
to deter me.

- I like how you then go on to explain that not only are you far away, you know it is a long road up there full of things which will put you back. Perhaps these are things which this person already does when you get a bit closer to them?

My heart would be
in less danger
if it were
to do cartwheels
in a mine field. coming up with this.

- This shows the affect this is having on you, because the thought of doing cart wheels where you will be exploded into bits, shows how greatly your heart is hurting from this distance. It is like you think you would have better chances crosses the mine field than you would be to get to this persons heart.

A really great small write. Well done.