the only types of generational curses i've heard of are from movies. [Practical Magic for instance] what is the curse exactly? it could be in your head, meaning you have a bad day and your mother tells you it's not your fault but the family curse. eventually you'll start to believe everything that goes wrong is the curses fault, feeding negative energy into something that might not even be there to begin with, which can result in cursing yourself.
i suggest a cleansing and protection spell. everyone effected by this curse should have a cleansing bath, then cleanse your whole house. wash everything with a cleansing brew, and finally burl sage, wafting the smoke into every inch of the house. when you're done, cast a protection spell or make a charm for your house, yourself, and everyone who has been cursed. recast the protection spell once a month until you feel it's gone. daily energy work and shielding can also help protect you from negative energy.