Helping Mom with finances..

So my mom has always been terrible with money. Long story short she's in a lot of debt and spends way to much for things she doesn't need (eating out, coffee, nails ECT)

Well, we live in our grandparents house and they are more than ready to sell it.

They are selling it to my mom for 205,000 which is an amazing price for the house.

They are gifting the down payment so that her and I will have a place to live and also so I can have a stable place to raise my son.

If I had credit id try to get the house myself but that's just not realistic.

My mom for whatever reason keeps putting off calling the mortgage company. Says they won't accept her blah blah...

She always says she's broke yet goes and buys stuff I'd mentioned above.

She could get a mortgage. She needs her husband (they don't love together) to co-sign though but he won't for again whatever reason.... Idk.

I want to be able to help my mom with her finances so that we can keep the house and not have to go to some small shitty apartment that's going to cost more and give up so much that we have including pets.

My mom doesn't understand it and it pisses me off. It's not just her she's going to be putting out. She's also going to put me and my son out and I'm not stable enough to do that... Neither is she and she can't go live with her husband because he doesn't live close to her work and she can't transfer jobs yet.

I just feel so pissed off at her. My mom won't listen to how serious this all is..

Small edit..

I'm 20 and working but currently don't have a working car of my own as I'm working to rebuild the engine. I had to move back in with my mom after leaving my abusive baby daddy. My family is very close with each other and would never just kick anyone out.

Maybe I am blaming my mom but I only want her to better herself.

Once I get my car up and running I could get an apartment with a friend and her kids..

Idk I think I'm just attached to this house as it's one my grandparents built and in reality there isn't a better place around for the price. I'd be mad if my mom let this place go.