Hang in there. You should get some good info here.
But first, what type of surface are you painting? Clapboard? Composite Board? Cedar shingles? Describe the material if necessary.
My first guess is that your problem is in the priming. If you have cedar shingles and they've been sealed at some time(s), and, you put a latex primer on, you will probably get this type of reaction. I don't think a latex primer and an oil-based sealer on your original shingles will 'mix'. You may have to use an oil-based primer this go-around. And from there on out, go latex. Do you know, for sure, if an oil-based primer was used when the final top-coat went on?