OK , so don't see her any more if she makes you feel bad. She lives far away , you do not have to.
If she has money then she will not need your financial help , I would resign myself to never seeing any of it....The blunt truth is that we do not need their approval, it is what we think of ourself that matters. It is a great pity that you and your son do not enjoy a warm Grannie relationship but it cannot always be helped.
I seem to recall a scripture that said "As far as it depends on you.....be peaceable with all men. Sometimes it does not depend on us - they make it imposssible.