Hi C. - I feel your pain and have been there!! In my opinion, CIO may or may not work for you/your family. It really all depends; I recommend trying various tricks/techniques at different point, experiment until you find what works. Just make sure you're doing something you feel good about.
At 8 months, CIO did not work for my daughter. I tried letting herself cry herself to sleep at night b/c I got desperate and she was at a point where she woulnd't even go down on her own. DID NOT work, b/c she was up within the hour. I'd go in, nurse her, and try and get her back down in her crib. When that didn't work, I would just go to bed with her. Regardless of when she went down or for how long, she always wound up in our bed generally before midnight and would nurse off & on all night. This lasted until she was almost 1 year. I loved sleeping with her and never had a problem with it - it was a good arrangement for the whole family for a while. But by the time we got to 10-11 months, I found that the quality of our sleep was decreasing. She seemed super restless and I wasn't sleeping well either...
So... I started by going in to comfort/nurse her when she would cry. If I couldn't get her back to sleep or if she woke up when placed in her crib, I would tell her I love her, but it's nighttime & time to go back to sleep. She would cry, but generally for only a few mins (sometimes as much as 10 mins). It was no fun, but I did this with her for about a week... Then I got to the point where if she'd wake up crying, I'd give her a couple mins to cry before I went in. Amazingly, she started sleeping through the night! Now, at almost 14 mos, she occassionally will do a little shout out in the middle of the night (cry for a couple mins), but she is generally right back to sleep. I look at my clock when she starts and would go in if it kept up... but often times she cries, then is silent, then cries, silent and so on for maybe 10 mins. When I notice those gaps between the cry & the quiet expanding, I give her a few more mins to settle down. She always does.
Sorry for this long post... but the sleep issue is so hard and everyone has an opinion (CIO is inhumane, CIO is the only answer!!)... You just need to figure out what works for you guys and makes you all happy & well rested! Both my kids co-slept with me, and I am happy to say they are both sleeping well on their own now! it's hard for sure, but hang in there and be patient - you guys will figure out what works :)