To be honest I would move with DH I dont know how I could libe apart from DH for weeks on end we like each others company so much, but if its working then its up to you. Have you discussed this with DH I know the beach sounds great but you wouldnt be living there all the time and there will be times that you need your DH company. The beach isnt everything. You have to think of the family until itself rather than move just because the area is better does your DD miss her dad and most of all do you miss him maybe list all the pros and cons of both moves and then discuss it as a family and think of all the money you could save to do things as a family when he isnt working.
good luck with your decision I hope my comment helps
same. we hated working apart, and that was before kids!
id move to the work town, then holiday at the beach when his week off and school holidays match up.