If you can quote from the whole passage, there will probably be a contextualising example somewhere before or after it.

Sure.
The text is actually from a paper on marital conflict. The author is proposing a theory that marital conflict originates, in part, from the specific breaking of a set of "rules." The author states "In large measure, significant conflict--that is, conflict that is both phenomenological painful and enduring--arises and continues when the "rules" of the relationship that are central to either partner's sense of self are...violated."

I'm really trying to develop my own understanding of phenomenology here. When I read this excerpt I thought "what's the difference between something being "phenomenologically painful" and something being "experientially painful"? I'm not all that interested in "pain" or "marriage" or the like....I really want to better understand the difference between something that is phenomenological and something that is experiential.

Thanks

My reading of that passage is that "phenomenologically painful" means "experientially painful" and both adverbs are superfluous because all pain is experiential, unlike a rock, which has an existence outside of experience and it might make sense to distinguish a phenomenally existent rock and an actual rock.

That is, remove the word "phenomenologically" from the sentence and the sentence will mean the same thing.

when the "rules" of the relationship that are central to either partner's sense of self are...violated. — Learning to die

I know from my experience that communication is everything in this situation. It can take time to reestablish, but it is worth doing. Eventually a channel opens.

I agree that 'phenomenological' and 'experiential' are synonymous in this case.

(The 'rock' example is irrelevant unless you are claiming that 'sense data emanating from physical objects or situations' is a necessary aspect of 'experiencing'. Later phenomenogists would dismiss the concept of 'an actual rock' and would claim the two adjectives are always synonymous, An alternative adjective of 'illusory' might be applicable in cases of consensual dispute about 'actuality').