rubbish relationship

[Eugene2114]

Hi,
Hearing the news of her picking up six Grammies in a night couldn't but share her joy, still couldn't make it out of her phrase (the second, of course.)
Thank you.

"First of all, I want to say mum - girl did good. This record is inspired by something that is really normal and everyone's been through it, which is a rubbish relationship."

[Dozy]

It is not totally grammatical. She is saying that the record is inspired by a "rubbish relationship" (a bad or failed personal relationship, presumably with a boyfriend). She is furthermore saying that such a relationship is "really normal" and that "everyone's been through it" (i.e. everyone has experienced such a relationship).