Hi, straight, SBF, 51. I just got finished with my first cruise. I went alone, with the attitude: NO MATTER WHAT, I WAS GOING TO HAVE A GOOD TIME!
Bring yourself and that attitude and you will have a great time. You will not 'stand out in the crowd.' There are so many people there on the same mission as you whether they are alone or with others. That mission is to enjoy themselves. Furthermore, the ship is so big, that you rarely see the same people twice.
Anyway, if you do stand out in the crowd, you may get noticed by other stand out in the crowd people -- smile.
I went alone and had a great time (I got tired of asking others to go with me). I now prefer to go with others because I want to experience and share with others the sheer delight that crusing has brought to my life. By the way, I plan a goal of 2 cruises per year.
Enjoy all of it -- it is a great thing that you are doing for yourself!