your rating only decreases if you lose.
I really don't agree with this idea. You already have the choice to not play with someone who is higher rating. Moreover, 100 rating is not really enough to justify rejecting them. I think if you are worried about a player with 100 rating higher then you're not really even trying to play rated. You might as well play unrated if you're not willing to play another player who is + or - 100 rating to your rating.
If you only want to play players who are near your rating then why bother playing rated games at all, that's not really the point of the ladder/ratings.
my suggestion would be to play unrated.