I know of a person (let's call her Gertrude) who decided around the age of 60 to stop referring to herself as Gertrude and instead opt for Gerty.  (Sorry to anyone who knows this person and/or is related in some way; I mean no offense.)  I find this incredibly odd.  While I agree that Gertrude is an awkward name and that perhaps Gerty has a more modern-sounding or more easily-pronounceable ring to it, I don't think it's acceptable to decide to change your name later in life.  My simple argument is this:  How did you cope for the first 60 years?  Surely you can find a way to cope for the next 40 or so. 

It would be one thing if you just recently moved and started a new job where no one knew you.  You could finally get rid of that outdated name and adopt a nickname you've always wanted.  Such is not the case with the aforementioned Gerty.  She's been living in the same town for quite some time, has attended the same church for a while, and has many friends, family, and acquaintances in the area.  From what I understand (and I could be gravely mistaken, though I don't think I am), she woke up one day and thought, "Ya know what?  I'm sick of my name.  From now on, people will call me Gerty." 

It's like if I suddenly decided to be referred to as "D".  It probably wouldn't go over well.  And most likely, instead of people complying with my new nickname, they'd probably assign me alternate ones, like "Dork" or "Dumb" or "David H. Hosier, formerly known as Dave, eater of baby flesh and destroyer of souls".  Family members and friends would forever ask me, "Changed your name recently? *stupid chuckle*," to which I would sheepishly reply, "Nope, still going for D."  Perhaps if I was 60 and/or had the unfailing respect of my peers, I could pull something like that off.  But as it is, I'll probably just stick to Dave. 

Name changes are a very teenager-centric thing.  That's when you're finding your identity and rebelling against everything.  The best way to express your feelings is to rebel against your identity by creating a new name.  Or a new spelling.  Instead of Jennifer, go for Xeni (pronounced "Jenny").  Instead of Tom, go for Thom (pronounced "Tom").  You're young enough that it'll probably catch on before you stop caring about it not catching on.  But if you wait until you're 60 to change your name, don't expect it to catch on.  It's too late.  You missed the boat.  The name you were given is the name you're stuck with.  Sorry, Gertrude. #sociology