I'm so mad I want to use my announcement to sting my parents (*rant*)

(Okay, a long, personal rant. Sorry. I'm just really upset.)
.
Without going into a long discussion about my pitiful life, just realize this. Ever since (11 years ago) my brother got his girlfriend pregnant (he eventually married her and they have 3 now) all I hear constantly from my family is "we have to help him. He has those kids, you know."
I've never minded my family helping my brother. What really pisses me off is they will use all of their resources for him and I have literally been told things like "don't expect us to help you," or "we'll make it even when we die." That, thankfully, will we at least 30 years from now. Which is NO help. How does 30 years of financial assistance "even up" when I'm in my 60s?? It doesn't. 
.
So here's the thing. My brother works full time and has a good job. He makes 6 figures (although that is NOT) a lot of money in the place we live. 
.
**I should add some background in here. We both, my brother's family and my husband and I, live on the same property my grandmother owns. He has his own house next door, rent free. I live in the same house as my grandmother, take care of her, and have always paid her (below market) rent. By my living here my parents don't have to pay for a nurse to come every day, or put her in a home. My husband and I also cannot afford to live in this area on our own. He would like to move back to where his family lives. I would like to stay near here because my mother is here and I think it's a better place to raise a family, but without our current arrangement we'd have to move away. **
.
I am pregnant and was going to tell my parents (and my husband's parents and everybody else) about the baby on Mother's Day. Then, yesterday, my brother told everyone he bought a house like 4 1/2 hours away. So now my parents and my brother have convinced my 88 year old grandma (that I live with and take care of daily) to sell off the only property she has to sell (a place worth maybe $500k) to GIVE MY BROTHER ALL THE MONEY so that he can own his new place outright (it's less than $250k) AND rent it AND keep all the rent money. 
.
I just can't f***ing stand the hypocrisy and how unfair this whole thing is. He doesn't live with or take care of her now. He's just the favorite (literally since birth only because he is a male). She just wants him close by. And my parents are for it because they don't want to see him move away. 
.
Nobody is throwing money at my feet! My husband and I both work and make less than my brother. And we live here to help the family, when my husband really doesn't even want to live here. And when my mother said what a tragedy it was that my brother bought a house because she won't have constant access to those grandkids I wanted to spit in her face and blow all of my big reveal plans and tell her that he's not going to be the only one with offspring and if this happens I am willing to move away just on principle after this huge straw of throwing money at my brother breaks my back. Then my grandmother would have to move in with HER. And since she will have given away all of her assets my mother will have to pay her bills until she dies. 
.
I'm mad. 
.
My husband said that my mother will always remember how I told her about the baby, though, and that I shouldn't ruin the surprise I planned. 
But I'm pregnant. And I'm upset. And I'm disgusted by this whole thing. 
.
What should I do?
.
.
And I don't know how to make paragraph spaces that don't disappear in this app. Sorry if the place savers bother you.