Tempted to come out to mum

I need to vent.
My mum is homophobic, and if she knew that I am bi, it will not go well.
I am so tempted to tell her I am bi, just to get her angry. I know it is not right, and I am using every ounce of will power to refrain from telling her.
A little history, I am the youngest of 5; 2 older sisters and 2 older brothers. Mum has always had her favourite and everyone knows that, and that is my brother 2 years older than I. He has gotten away with everything, from stealing my money when I started working at a teen, to selling my parents' belongings, name it he has gotten away with being a drug addict. It has always bothered me, and because he is such a bully and mum will take his side no matter if we're right or not, I have learned to let him be.
My husband and I celebreated our 14th wedding anniversary in August and it was special because we made it through hell. My parents were out of town, so yeah. Now, my brother celebrated his annversary with his wife yesterday and my mum gave him her vehicle! Second vehicle in less than 2 years! Not to mention a snowmobile. . . I know material possession is not important but the fact that she can go above and beyond for one child and leave out the rest of us has gotten to me.
I should be thankful that I am independant and do not need to rely on my parents for anything, but at least a card would have been nice!
I know it is not a good idea to come out to my mum while I am angry, but I am so tempted to do so just so I can at least know she feels anger as I am.

 

Thank you, I feel so much more content with my situation. I will still be able to take care of myself when they are gone and my brother won't. Karma will do it's job thank you for listening