As an e4 player, what do you hate to play against

come on mate this 3.nc3 idea as a refutation has been outdated for at least a decade.

it is now well known that 1.e4 nc6 2.d4 d5 3.nc3 dxe4 4. d5 nb8! 5.nxe4 c6 almost immediately equalizes

Yes, this is true. Actually white can try playing Blackmar-style 5.f3 (and this position may also come from a Blackmar) and enjoy a reasonable compensation for the pawn. However, Black can decline with 5.f3 Nf6 6.fxe4 e6! with a fine game.

Bg5 with the idea of Qd4 or Qe2 and O-O-O seems decent

Petroff

I'm not the biggest fan of playing as white. I also prefer playing the Reti Opening as a waiting move to see what my opponent does before playing e4 or d4. But when I play 1. e4 probably the Sicilian is my least favorite to face as my opening prep is either lacking or playing a VERY dubious form of the Alapin with Bd3 Bc2 b3 Bb2 aiming both of my bishops at a (hopefully) kingside castle.

when they beat me

sicilian

I don't like taking risks either but I recently changed to 1 e4 because of the book Keep It Simple 1 e4.  It seems to me the repertoire helps keep risks down. For instance, you mention 1...e5. Against that the author Christof Sielecki uses 2 Nf3 and then after 2...Nc6 plays the other knight out 3 Nc3. After 2...Nf6 3 Nc3 again. If it reaches the Four Knights he plays the 4 d4 (Scotch Four Knights) which is a fairly safe though sort of drawish opening. If In the Petroff black wants to stay within Petroff realms he can play 3...Bb4 but then white can enter a Berlin Reversed a tempo up, once against rather safe. 

I don't like to take risks but I enjoy closed positions where it is more maneuvering. I am not able to easily handle open positions very well, and I prefer to keep as many pieces and pawns on the board as possible.

I do have a 1.e4 repertoire that somewhat fits my criteria, although I would never dare try it in a serious OTB game. Against 1...e5, I play the Ruy, and then exchange (no matter what) and then proceed to play the resulting structure. 

Against Hippo-style openings, I've found success in playing e4 d4 c4 Nc3 f4 Nf3 Be3 Bd3 Qd2 Ke2 and just moving my entire structure towards the enemy. Since they're playing useless waiting moves, just play useful waiting moves by taking all of the free space and then taking the time to sit and think about how to best defend it. I hardly lose those games anymore, since the players who play Hippo-style usually don't actually know how to play a closed game.

Exactly.

Actually, I don't really know why, but I absolutely HATE the sicilian defense.

Do not ask me why, I don't know.

^^ because it's nasty?

c5

What??? No Center Counter Defense?

Most you e4 players throw some serious hate my way... what gives?

For me the most difficult to face is clearly the sicilian. Which makes it the most annoying.

Second place probably goes to the french, because white can't avoid it and it's hard to get much interesting happening against it. Still, white usually gets a good position so I don't really mind too much.

I play the Vienna so I don't encounter the Petrov. CK I am thrilled to play against. If you hate facing the CK... I think you just need to study whites options, there are many good ones.

The center-counter is a joke.

If everyone played the center-counter, I'd be an e4 player.

The Alekhine Sucks, but I have trouble with positions featuring the big, mobile pawn center, and hence why I hate the Grunfeld and Alekhine, but that's a personal issue.

The REAL problem with 1.e4 is 1...e5!

I'd say Sicilian Defense, Ruy López Opening: Morphy Defense, Alekhine's Defense and Pirc Defense.

I like open and not complex games, and I don't want my Bishop to be kicked (I'm a Ruy López player).

And I hate Sicilian because I don't want to trade my d-pawn for c-pawn, also I can't play the Ruy López.

Same

I rarely play e4, as I'm strictly a King's Indian Attack player but when I do, I hate playing against the Caro-Kann defense.