You're going to get a lot of differing opinions, and what works for one person/family may not work for you.... Every child is different, and every child has different sleep patterns.
I did not want to do CIO. I did not. I read several books (Dr. Sears, the No Cry Sleep Solution, etc.) and some of the tips helped a little.... But I decided to read Dr. Ferber's book on kids & sleep (he's the "CIO" guy; a PhD and a physician and has worked with kids and adults with sleep disorders for many decades). Anyway, when I read it, I realized that this was what we had to do. I followed the recommendations in the book, and was finally able to sleep in my own bed and my son sleep in his crib. Yes, it was AWFUL for the first 2 days (the first day was worst), but the next week, when we'd finished and our son was sleeping in his crib, and I wasn't crabby, and I was able to snuggle with my DH...... our whole family was happier, and I was a better person, literally, because I was able to sleep and be rested, so I had more patience with myself, with my son and with DH and could deal better and be a better employee....
Since doing it, we've had to do it 1 once or twice more, to varying degrees. My son was a "head banger" (he'd bang his head in frustration--very scary), so we wrapped and sheets around the crib edge so if he did, he could bang his head and not get hurt. Also, if he's a climber, be aware that he may try to climb out of the crib (our son did once, around that age, and fell, but I had put pillows around the edge of the crib, out of paranoia, and he was scared and never did it again).
That being said, if I think my son is sick, and wakes at night, I always go and see him.
I had come to the conclusion that for the sake of my sanity and my marriage, I needed to do what I had to (within reason) to ensure I could sleep through the night. It was not pleasant, but it was worth it.... If you don't think you can do it, tell your DH you need his help breaking this habit, and have him do the hard part (sleep at the opposite end of the house, if you need to).
Also, if you go this route, think through, ahead of time, what you want his bedtime routine to be. Give some thought to it, and then implement it on the first night you're going to do CIO (the first night is the worst, and the subsequent nights get gradually better--it took 3 or 4 nights the first time for us). And I definitely recommend reading or at least skimming Ferber's book before you start, so you can get an understanding of how/why it works and what's actually going on.