It does feel wrong, very wrong, all your instincts are screaming out for you to be with your child. It doesn't help if you don't have a supportive partner, mine was a damn sight tougher on cc than I was!
But look at it this way, I know loads, literally loads of mothers who still get up in the night to comfort their 3/4 year olds, because they've been doing it since they were babies and it's a habit. I know loads who have to co-sleep with their children because again, it's a habit. These mums are literally tied to their babies, they can't go out in the evenings because their children need them there. Eventually it destroys your social life. Ask your dh what would happen if you both wanted to get a babysitter for a night out, could you do that the way she is right now? And if you carry on like this, the habit becomes more ingrained and it gets worse.
Yes it is hard and very upsetting to do cc. This is what I would do. The first time she cries I would go in and (without speaking to her at all) check her nappy, offer a drink, make sure that she is comfortable and that there is nothing wrong. If her nappy is fine, she is not ill or thirsty, then you know that she is not in any physical discomfort so it might make it easier for you to leave her.
Go in every 10 minutes, just to reassure her that you are still there. Say to her "go to sleep" in a stern but quiet voice (repeat this in your head like a mantra to stop you from saying anything else), tuck her in and leave. Do this every 10 mins. If she is still crying after 40 minutes, extend the time period to checking her every 20 minutes. If you do not give her any attention, and she knows exactly what you will say, she will give up.
The first night is always the worst. Ds lasted for 2.5 hours I think. I hated every minute of it! But the next morning he was his bright and chirpy self, it hadn't affected him at all. The second night she will cry for a shorter period. The third night she should hardly cry at all. Be consistent. You have to make a plan in your head. Tell your dh what you are going to do and stick with it. Take on the responsibility if you like, it's just for 2/3 nights, remember that.
Your dh will thank you afterwards when she goes to bed without fussing and stays there, just think how good you will feel then!
By the time I see you in the pub she should be sleeping through!