I am not uncomfortable with multiway pots, but its just simple math, that you are going to win them less often. If 4 players see a flop, each can only win 25% of the time, and this number does not change dramatically, just because you were the preflop raiser. So for many the biggest adjustment is a mental one, because they need to give up on the idea, that just because they raised preflop, they have some kind of right to win the hand.
If you raised UTG, got 2 callers with position on you, and then BB called as well, then the value of you being the preflop raiser is pretty much nothing, and actually the player in position is the one, who have the best chance of winning the hand. So you just need to play the hand in a very straight forward way, where you only put chips into the pot, if you have a good made hand or a good draw, and otherwise you simply get out of the way.
You also need to adjust your idea about relative hand strength, because more players can have a very strong hand. If you are against a single opponent and have


on




you are very likely to have the best hand, but if 3 opponents saw the flop, its much more likely, someone might have a hand like


or


and be ahead. So in the latter situation you need to play a bit more of a pot control game and perhaps even be willing to fold your cowboys, if for instance the other players start raising each other.