Don't burn your bridges....
I have lived here in Sosua since Aug 2006 and I came from UK with my partner. We have two young children of two and four years old. We moved here with relatives already in place, so we had lots of good contacts and advice before we came.
My advice is to try living here but not to `burn your bridges' with regard to being able to return to your previous situation if things don't work out. I understand that you're retiring in your early 30's which means you're in a very fortunate situation. However, the money you've accummulated can disappear very quickly here, so I'd suggest you come on your own and try living with your own small family before dragging along others who could seriously turn into a millstone around your neck.
I own my own property, but with private school fees, high cost of petrol and some groceries I find that I'm spending a similar amount to that which I spent in UK after paying my mortgage. We only eat out about once a week and a bit more during a holiday like last week, because it's generally a bit of a nightmare eating out with young children. We do buy Dominican Lunches for 100 pesos and we do eat dominican food at home along with fresh fruit and veg and the sort of healthy food we ate in England. I buy veg and meat in Charamicos when I can, which is a Dominican area where things are cheaper than in the expat supermarkets. However, I've been keeping close track of our spending since we came and we spend approx 700 to 800 dollars a month just on groceries. Electric can also be very expensive here. Prices fluctuate all the time for no apparent reason. Petrol has gone up at least 25% since we came and cigarettes for my partner have gone up by over 70%.
When you first arrive, you tend to spend a lot of money on stocking up a basic home, things such as furniture, electrical items, household stuff etc. Even if you buy or rent a furnished property, you will still want your own things. Also, you will need a car. We paid 9000 dollars for a second hand Chevy Blazer which has served us well. We already had access to a good mechanic who we took with us when we bought. I took the advice of people who had alread moved here and didn't bother shipping anything because of the `grief' and possible `unknown' expenses. Now that our spending has `settled down' I estimate that we still need approx 30,000 dollars per year to live one. That is just for a fairly basic lifestlye, with car and house paid for. I've spoken to other local expat families from USA etc and that seems to be the rough guide to a family of four. If you take that as a guide then on your 45000 dollars, you won't have enough to pay for the other couples, bearing in mind we spent far more than that in our first few months.
I like it here, but I have to say it doesn't `tick all my boxes'. My children love it and my partner enjoys his diving work. For me there is something missing, though I'm persevering because I know it takes time to get used to new things. I had travelled and back packed extensively to Borneo, Java, Bali, Thailand, Sri Lanka, Venezuela and Peru before having the children, so I was convinced that I would enjoy this lifestyle. However, travelling to and living in a place, in particular with a family and the limitations that brings, is a completely different `ballgame'. I have no regrets about coming here, because it was something that I needed to do, but I still don't know what the future holds.
So, I'd say, by all means come here and try it out. But don't bring other people with you or `cut all your ties' untill you're sure it's definitely where you want to be. Chris Colon's suggestions, whilst delivered in a slightly antagonizing manner, are not without merit, so don't discount them entirely.
Good luck with your decisions. Ultimately, only YOU can decide....