That is a great question. If the Russians were getting their way, the middle east would be a much more stable place than it is now, and there would be no Syrian refugees. What is it that the USA and our allies want?
Apparently, we want refugees. And by "refugees" we mean hundreds of thousands of able-bodied, military-aged young men in designer jeans, carrying iPhones and bogus Syrian passports flooding across our borders.
The Western world seems bound and determined to ensure this happens.
I'd say you answered her question about why we don't want Russia involved - they add stability which keeps the whole area becoming ISIS breeding central. We can't have that.