Mail Account Address Swiching

I have 2 accounts on my computer and I want to get rid of one of them. They both have different mail addresses, one is Live and the other (that I want to keep) is Gmail. I was trying to get rid of the Live one thinking it would completely take off the same account that I have to log into it before I can get into my computer and I could just use my Gmail mail address for my account log in. So I logged into the Microsoft account website with the Live mail address and tried switching the address to my Gmail one. Of course it said I already had an account with this email, so I logged into the Microsoft website as I did before but with the Gmail account and completely removed/deleted/eased/I don't know the term it used/got rid of it still thinking it would get rid of the signing in Gmail mail account too, but it didn't. I would have removed/deleted/erased/I don't know the term it used/got rid of the Live account but I had purchased the word/PowerPoint thing on the Live account and I didn't want to by it again. So I logged on the Microsoft account website with the Live account and tried adding then changing the Gmail mail address to my primary address then deleting the Live address but it said the Gmail account could not be used. Is there a solution to this or am I just stuck with my Live address and account?