A few things worry me about your DH OP. The lack of motivation (does he just procrastinate generally) and the unwilling to commit to future plans (I can sort of see re joint savings account but not re holiday etc).
For the amount of time you've been together and engaged and married this would seriously worry me! Did you suggest moving on, buying a flat etc or was he railroaded into it?
He really doesn't seem at all mature for his age and sadly men of this type generally don't change, at least not until it's too late, or then when they're in their late 30s/40s they magically settle down as all their mates have done it now and had kids etc and it's harder to pull as a sad fucker at that age. In fact 3 men I know who are finally married at 40 and 46 and 41/42 respectively spent years rushing around dating younger very attractive women, the 41/42 year old dated a couple at a time, then the 40 year old met someone who was his match but also who he felt secure with (he was very insecure deep down), the 46 year old dated a woman a similar age to him with a DD but also someone who stood up to him (he proudly said about some of his exes that they were younger, more attractive and not as clever as he thought he was...
and the 41/42 year old had lots of female friends etc until he wanted to date me (I said no, not whilst you're dating 2 women), then he ditched one, kept another, I went off with someone else meantime, then he moved abroad for work met someone younger who insisted the female friends were ditched (which he did) and got tough with him, he got engaged soon after and also she needed marriage to stay in UK with him.
What I'm saying is some men aren't ready or are ready at very different stages for marriage - you can't compartmentalise them and you can't change them.
If you wait years for him to deal with his issues you could be missing out on the man of your dreams whilst your DH here potters along getting older and older, divorced now, lonely whilst you're with someone great.
Think about this, it is very very hard to get someone especially a man to change their mind when they don't want to do this!