To answer your question, I reviewed the following article:
https://www.lawyersmutualnc.com/blog/the-difference-between-me-myself-and-i
I engaged this article, as I felt as though if I were to answer the question from personal experience with this grammatical issue, you might not give my answer as much credence. I thought it would be a good idea to provide a secondary source as evidence.
The author of this article attributes motivation for using myself to the following factor: "me" sounds less formal, perhaps less official, and may inspire less faith in the writer using “me” because it is not as seemingly formal and as seemingly official as "myself." However, "myself," as the author points out, is often misused even though the user's intentions for using "myself" are legitimately-motivated.
The author writes, and I will quote what he says because he says it more effectively than most people I've encountered (that are attempting the same explanation of when to use "me" or "myself"):
"Keeping Myself in My Proper Place
Here, then, is a quick summary of how to keep me, myself and I straight.
- “I” is a first person singular pronoun that is used as the subject of a sentence or clause. (Example: I write the songs.)
- “Me” is used as an object. (Ex: The songs are written by me.)
- “Myself” is a reflexive pronoun used when you are the object of your own action – i.e., when “you” are doing something to “you.” (Ex: I could write the songs myself, but they sound better when they are written by Barry Manilow and me.) Other reflexive pronouns are herself, himself, yourself, itself and themselves.
Confusion creeps in because although “me” is an object pronoun (Ex: Barry Manilow hates me), “myself” usually occupies an object position as well. (Ex: I hate myself when Barry Manilow doesn’t like my songs.)
Notice, though, that in the first example, the subject (Barry Manilow) and object (me) are different. Thus, the object pronoun is correct. In the second example, the subject (I) and object (myself) are the same.
“Think about looking in a mirror and seeing your reflection,” writes the Grammar Girl. “You’d say, ‘I see myself in the mirror.’ You see your reflection. ‘Myself’ is a reflexive pronoun.”
You can also use reflexive pronouns like “myself” to add emphasis to a sentence. Used this way, they are sometimes called emphatic or intensive pronouns. (Ex: I myself heard the gunshots. I wrote the brief all by myself.)"
Available at: https://www.lawyersmutualnc.com/blog/the-difference-between-me-myself-and-i
What is of paramount importance to take away from this is the following: as the author says above, "myself" should be used when you are trying to articulate how you have done something to yourself. For example, you would use "myself," when you are saying something like, "I did this to myself." You would not write, "I did this to me." In addition, it is of equal importance that the author mentions that proper uses of "myself" may be engaged to emphasize the use of "I."
By contrast, using "myself" to say something along the lines of, "Melissa, Steve, and myself wrote this." is incorrect. Another way to look at this is as follows: eliminate the other entities (i.e. Melissa and Steve), and then articulate how you wrote whatever "this" in the aforementioned sentence refers to. (Forgive the preposition at the end of the sentence I just used. However, as Winston Churchill joked, when he was criticized for often using a preposition at the end of a sentence, "This is the type of errant pedantry up with which I will not put." He was referring to the grammatical rule regarding prepositions at the end of sentences, when he said "errant pedantry. That said, plenty of famous and critically-acclaimed authors, such as even James Joyce, violated this preposition-related rule on a regular basis.)
Forgive the lengthy parenthetical. I will return to the point. In the aforementioned context, you would not say, "Myself wrote this." You would say "I wrote this." Remember how the author of the article mentioned above writes, "'I' is a first person singular pronoun that is used as the subject of a sentence or clause. (Example: I write the songs.)" Because "I" is a first person singular pronoun, the proper and grammatical structure would be, "I wrote this," when you are trying to articulate how you co-authored what you wrote with Melissa's and Steve's help. Once you have more easily identified the proper construction by elimination of Melissa and Steve from the sentence, you would of course revise the sentence to reflect their co-authorship.
I hope this helps. I loved your question.
