An NFP and an SFJ. So, you're telling me 86% of SFJs are satisfied while 53% of NFPs are. LOL!There are too many variables to tell for sure. I would assume that extraverted types dominant in Ne, Se, Te would be most comfortable with making a new move, moving out of an old relationship, meeting a new person and developing a new relationship.
Overall I would say that types that are most likely to divorce would also be those that are least happy in the relationship. This depends on their partner as well. As far as MBTI goes here are some statistics. I'm not going to re-type this so I'll just post up a picture. Nitou is right in that two SJs together report higher satisfaction. NF-NF pairing is not far behind and next best choice for NFs is NTs. Seems NTs report to be happiest when paired with NFs and next best choice is other NTs. Both NFs and NTs don't seem to be so happy when in relationships with SJs. Lowest mutual satisfaction in relationships was reported between STJ and NFP partners. This is all on average of course.