Is this C++ program correctly implemented in SSE?
Your SSE code looks like a reasonably accurate translation of your original C, but that C code doesn't immediately jump out as the best way to do things. In particular, I don't see where you gain anything by taking the absolute value before you do your multiplication. Given that your're squaring the value immediately afterwards anyway, it would appear simpler to just leave it negative if that's what it happens to be. Lacking a specific reason to do otherwise, I'd start with something simpler, like this:

double x = x1 - x2;
double y = y1 - y2;

double dist = sqrt(x * x + y * y);


Then I'd convert that to SSE instructions.

Especially if you're concerned with speed, you might want to consider using an alternative to the Pythagorean theorem to compute the hypotenuse though. I posted some C for one possibility in a previous answer.