Never use "myself" as a simple subject (for "I") or object (for "me")—it should only be used in very particular circumstances. Use "myself" (and other pronouns ending in "self") only reflexively (where the subject and object are the same person, as in "I see myself") or to add emphasis ("I myself was there!").

The problem with the underlined portion is the conflation of "someone" and "themself." This confusingly places a plural, "them," into a singular form to match it with "someone." To clean up this awkward phrasing, the best choice among the answers is "people who have hated themselves."

The underlined portion of the sentence needs one change to one word. "There," indicating a location, should be changed to "their," the third person plural possessive. Thus, "on the trail up ahead of their path" is the correct answer choice.

The use of "myself" in the sentence is incorrect, as "myself" is a referential pronoun, but has nothing in the sentence to refer to earlier in the sentence; therefore, "to me" is the correct answer choice.

The use of the word "it's" is incorrect in the sentence, as "it's" is only the contraction of "it is." The possessive form is always "its," making the correct answer "due to its massive length."

The use of the pronoun "myself" in the sentence is wrong, as it is the only use of a first person pronoun, and needs a previous usage to refer to; therefore, the word needs to be changed to the simple first person pronoun, "me," which makes "The issue was first brought to me well over five years ago," the correct answer choice.

The use of the reflexive pronoun in this sentence is incorrect, as there is no previous use of the first person pronoun to which it can refer. The word "myself" needs to changed to the simple first person objective pronoun, "me." Therefore, the correct answer choice is "a great deal of anger toward me."

The use of "them" is imprecise, as it is unclear who exactly "them" is referring to in the sentence. To clear up this confusion, the use of "themselves" is the best way to indicate this usage refers to the subject of the sentence. "Themselves to watch their own weight" is the correct answer choice.

The use of the reflexive pronoun "myself" is incorrect when it has no previous first person pronoun to refer to. "Myself" must be replaced by the simple first person objective pronoun "me." As the only answer choice to make this change, "The issue was brought to me" is the correct answer.

The key grammatical issue in the sentence is that two homonyms are confused, creating a mispelling in "they're." "They're" is actually the contraction for "they are," while the sentence needs the third person plural possesive form. "On their side" is the correct answer choice.