Here the 1841 British edition, probably because of the my in the following “my sincerity”, ended up with “my afflictions” rather than the original “mine afflictions”. Elsewhere in the Book of Mormon, given the word afflictions, the possessive pronoun is normally mine (eight times) rather than my (once, in 1 Nephi 15:5). The dominance of the mine form here is statistically consistent with two occurrences in the text of thine afflictions but none of thy afflictions. (There are, it should be pointed out, no examples in the Book of Mormon of the singular “mine/my affliction” or “thine/thy affliction”.)
The 1841 change was undoubtedly accidental. Notice that there is another occurrence of mine afflictions in this same passage: “therefore I will cry unto thee in all mine afflictions” (Alma 33:11). This other instance was not changed in the 1841 edition, nor were any of the seven other instances of mine afflictions. Moreover, this occurrence of my afflictions in the 1841 edition was never perpetuated in subsequent LDS editions.
Summary: Maintain in Alma 33:11 both occurrences of mine afflictions, the reading in each case of the earliest textual sources.