I actually agree with my mom.
I am not giving my fish away because I want a certain fish though. My friend really wants him, and before my mom and I talked about it I had already asked her.
I am always looking for bettas that need to be rehomed (harder than you would think), so if you ever feel like that is something you need to do just shoot me a PM.
Sounds like your friend is taking good care of the fish she has. As long as she can financially afford everything she needs for a second setup, it seems like your little guy would be ok with her.
I know how you feel. I just got a betta I felt sorry for from Petsmart. They let me have him at no cost. I'm moving in a few months and the last thing I need is another fish but I rehomed Little Dude and he is now happily settled in with my friend in Indiana.