I so can relate to what you're saying about tight finances.
My husband & I didn't have a honeymoon after our wedding and we couldn't afford any vacations at all for the first 8 years of our marriage.
We made a little "Irie Box" and we started putting $7-10 in the box every day. In order to do that we had to cut back on a lot of little things.
We don't have cable now (Just hooked up the television to our laptop and watch Hulu) , cancelled all subscriptions. We're on a family plan with our cellphones - we never buy new ones, just wait for our free phone upgrades.
We sold our car. (we live in San Francisco - parking garage rental costs 300$ a month - not to mention the cost of insurance)
I walk to work every day instead of taking the bus (A 45 minute walk, lots of hills.. phew!). Pack all my lunches.
After 3 1/2 months we had enough money in the "Irie box" for the plane tickets. 2 months later we could book the accommodations.
It helps that we don't have children yet... but we're planning to start a family end of next year, so this will be our last year of travel for a while.
I don't miss the things that we've given up because Life is about experiences, not having all that stuff.
You never see a hearse being followed by a U-Haul.
Good luck saving up for your trip! I recommend having a box and putting money in it. It's rewarding to watch it fill up, it also prevents the temptation to spend any of it before you reach your goal.
I really hope you'll be able to get back to Negril soon!