Just had a huge fight with my significant other

i just had a huge fight like no other, i’ve never fought (verbally) with my s.o. or f.p. but i just did. i left them feeling numb and like issue wasn’t solved because i couldn’t help enough. i feel worse and i feel that i don’t deserve them even after they tell me that it’s okay and i do deserve them. i’m not sure what to do because i only have the mantra going through my head of “the abused become the abuser.” i’m not sure how to help myself or them. all i know is i need to help myself first before them because “you can’t love someone till you love yourself.” anything will be appreciated. thank you in advance.