Anyone here do CrossFit for a while and then quit? If so, what did you do to replace it, fitness-wise, and how did it/is it working for you?

I ask because I think I'm at the end of the CrossFit experience for me. But I'm afraid to quit as I am in the best shape of my life. Problem is, I always feel worn out and am always battling little nagging injuries ever since starting CrossFit.

A little about me:

I've been CrossFitting for about 4 months now. Every month I've contemplated quitting, but then I just say to myself, "One more month." It's not that it doesn't work in terms of giving me a great workout, but the problems are:

1. I'm too competitive. But I don't have the fitness level to back it up. This is a flaw with me of course, not CrossFit. And it would be fine...if I were in better shape and better at CrossFit, but many of the movements I am not even close and never will be due to lack of flexibility (to that point where it is now holding me back from getting better with the olympic lifts) and in some cases fear (Handstands, rope climbs).

2. I'm constantly either injured or just feeling like shit.

A few weeks ago I was doing cleans when I tweaked my wrist. It took 2 weeks to heal. And I have a pinched nerve in my neck/back (never was definitively diagnosed because of my claustrophobia - couldn't go through with the MRI). That has been acting up the last week ever since going all out with a WOD.

3. I am not motivated by the community/group workouts. At times, I get kind of annoyed with the "Keep it up!" and "One more rep!!!" that I get mid-WOD from my peers. I know I'm not normal in this regard : )

Discipline isn't an issue for me, so I'm thinking about joining a local globo-gym as I am certain that I'll need to do strength training. I live in the Northeast so working out doing playground workouts is not going to be an option in another month or two, given the weather.

I am just afraid that what little fitness level I've built up over these 4 months will go away no matter what I do, as I have no interest in the high-rep/high-intensity WODs anymore. But a once per week doing a sensible (for me) HIIT session is definitely in the cards.