Divisible Duel

Alice loves working with numbers. One day, she takes two integers $X$ and $Y$ ($Y \ge X$) and becomes curious about the numbers between them. She looks at all integers between $X$ and $Y$ (inclusive) that are divisible by $X$. Among these numbers, she separates them into even and odd numbers. Let the sum of all even numbers Alice has be $S_{even}$, and the sum of all odd numbers she has be $S_