Something I have learned in my relationship with my boyfriend is that he is NOT my psychologist, therapist, or psychiatrist. I can attempt to have him understand the woes I am going through, but since he doesn't experience it himself it is very hard for him to deal with. It doesn't mean you stop communicating with them -- it just means that you can't expect them to solve all your problems. When you're in a long term relationship it is easy to forget that boundary. You expect them to know everything about you and you expect them to know the answers. It's natural.
That is when you have to pull back and reevaluate yourself. You have to make that distinction of what they can actually help you with and what they cannot help you with. Then you need to find a way to effectively communicate your feelings without 'blowing up.' The aim is to be non-confrontational and to create an atmosphere that is comfortable for both parties. You want him to understand, but you should not expect him to fully grasp the pain you are in. It is hard if you don't experience it yourself. (And even then it can vary because there are multiple variables in how people react to different situations)
I hope I helped a little.

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