That is very thoughtful and sweet of you to be concerned over your mouse being alone, so kudos to you.
But from what I have heard, the other responses you have received on the forum are correct when it comes to male mice. They do tend to fight a lot together and a single male mouse is usually the happiest.
This is of course the exception to the rule when it comes to small animals, as the pets I have had (gerbils and rats) DO need companionship with a buddy so as not to become lonely and depressed.
And female mice like to have friends to play with too, if I am correct? But male mice...well, not so much. Hard to believe but I guess they do get very territorial and cranky with other males.
I have never had mice personally, but I would tend to agree with the other posters, just based on what I HAVE learned from reading posts of other mice mommies. But I am sure there are people who do have more than one male mouse and there are no problems. Hmmm!