I've fallen in love with a married man. We haven't done anything other than hug and I don't condone cheating at all, neither does he. I know he's not just gonna up and leave his wife as he takes his commitments seriously.
But I feel so guilty every time I wish their marriage would fail.
How do I stop myself from wanting someone that is unavailable?
You said you know he won't leave his wife, so anything else you feel other than friendship isn't going to come to anything. Try to concentrate more on meeting people who are single if you're looking for a relationship. If you're constantly going for people who are already taken then I would consider looking into that more deeply.
It's not love, it's infatuation. How do you know this guy? Do you work with him? A friend? Nothing you say or think is going to change anything so there is no point in worrying about it. Keep a distance from this guy if you can.