It is really hard and makes it complicated doesn't it?
I definitely found the moving in or not decision to be complex. It's nothing like moving in with somebody before children, before children it's a fun time, casual sort of thing, figuring out if you get on or not, fighting over wallpaper, you can be fairly independent but you get to share a bed every night. What's not to like?
When you already have children it's a totally different ballgame - it means that your new partner is becoming a permanent fixture in DC's life, potentially causing upset for both if you were to split up, it means they have to take on the step-parent role which can be tricky, it's a huge level of commitment much closer to marriage than what we would normally think of as moving in together.
I would say that after 10 months it is far too soon to be thinking about moving in anyway - was it his idea that he was wanting to move in with you (but then scared because of the massive commitment moving in really is) or was it yours? I think the sort of in-between step in this situation is for you to start spending more time together as you, him and DC - days out, just hanging out at his house or your house, holidays together, then moving to spending more time at each others' houses as a sort of trial run (only really works if he has a spare bedroom for DC) and then if all of this is going well and it starts to feel silly living in separate houses then you would look to move in together. But it's absolutely paramount that he has a good relationship with DC as well as with you and this needs to be built up before moving in to minimise the difficulties which might come from introducing a "new parent figure" into the household.
I agree it's nice for dates with a new man to be about being you and not about being "mum" all the time, but to go from a totally adult relationship to being one with kids involved is quite a change in you and the dynamic of the relationship - it's hard enough when you have a baby as a joint decision, to have this as something that isn't part of the relationship (even if you vaguely know it is there) and then suddenly is very much there and present must be really difficult as well to adjust to - so I think as well as enjoying the time away from DC it's important to talk about DC to any potential new relationship fairly early on to make it clear that they are a big part of your life and if the relationship becomes serious then it's important to you that they like and show interest in your DC too. I don't think I would be able to date someone for long who wasn't curious and interested in my DC, even if I didn't let them meet them until later on, because to me it is so important that they realise the relationship isn't just about me.
It might be worth talking to your bloke and hashing this out and seeing if he's interested in taking it more slowly rather than rushing to the moving in part just yet, or whether he really is freaked out by the idea of being involved in a child's life in any way at the moment and perhaps he really isn't ready for that phase of life yet (in which case it's a shame he didn't say this earlier!)