I don't think you should have started it if not able to commit, but it's too late for that now.
the reason why I say that is that CC is unpleasant in the short term and although I do not think it is wrong, I think it is not a good idea to put you or the baby through that unless you are leading somewhere with it - ie the unpleasantness is taking your baby towards the gift of confident self-settling and lovely nights' sleep. Otherwise, it was just a random horrible night when the baby cried and no one picked him up.
I didn't attempt it at 6 mo but yes, I was the walking dead in those days - worst possible age for exhaustion imo, they feed in the night but are alert and demanding in the day - and heavy - and it feels as if it has been going on for Ages and will for ever. Don't blame you for trying.
IF dh is so confident, make him do it.
If he won't, or if you both decide to drop it, do NOT attempt it again until you are prepared to have the grit to see it through (at least 2 or 3 nights; I wouldn't think you could say it is not working before then, I have never had to do it longer than that, some people say give it a week)
If you do decide to try again, don't let anyone make you feel guilty about it, if you are doing it properly and going in and out at timed intervals etc (not CIO)