Yes - the ways to determine a connection can be very confusing the first time. It took me a couple of tries to figure them out. Here's my assessment and maybe this will help you.
If you are connected to the global tree, at the bottom of your profile, you will see a series of comments (so-and-so is xyz degress from Kevin Bacon, from AJ Jacobs, etc.). These only appear if you are connected to the global tree and are quite useful. The number of "degrees" is based on how far away you are from them genealogically. For example, I am 1 degree from my father, 2 degrees from my grandfather, 2 degrees from my uncle, and 3 degrees from my cousin. For each step it takes through the family tree to get to that person, add a degree. I'm also 1 step from my wife, 2 steps from the in-laws, and 3 steps from the grandparent in-laws.
If you don't want to use the links or don't have them, click the "Family Tree & Tools" tab, and from here you can scroll down to the "Relationship to Me" (about halfway down the page) and then put in the two people you want to check. This is the "Relationship Finder". This one only shows "blood relations".
You can also use the pull-down menus, click Find and Connections and go to the "Connection Finder". This one only searches up to 10 steps away.
I'd try both to see what results you get. My guess is that you can use the Relationship Finder to get what you need in this case.