whoops I don't think you are seeing the longer-term. You can't just ditch a marriage every time it hits a rocky patch, especially not if you still love each other, because rocky patches are normal, and if you have a basically good relationship, they will pass. Even more so if you are going through a financially difficult time!
You sound very emotionally reactive- of course if every time you perceive a slight, you withdraw sex or start arguing, then your marriage will deteriorate, he will be reacting to your bad mood/lack of interest in him, you then react to his perceived faults and so you go round in circles.
You need to learn to be together, argue together, and cope with difficult times without the boat tipping over. This guy hasn't suddenly changed, what's happened is you have started having a difficult patch (probably after the rose-tinted spectacles fell off after the lead up the wedding). Your marriage won't survive if every time this happens, you all look for the way out.
I would get some counselling yourself to talk this through so you can start to hear what is triggering all this upset/reactive behaviour, and where things really lie.
But if you want to get married, never have cross words, never get stressed and take it out on the other person, never have a difficult time when you have financial stress/change, may I suggest you don't bother!