i’m gay as hecc

i’m 13 and i recently got a gf i told my mum and she has always been really supportive because she is bi i used to go round for sleepovers to my gfs house all the time because she was my best friend but now my mum won’t let me anywhere near her bedroom which is kinda stoopid cuz i’m underage and now i won’t gay to see my gf as much now she is asking to tell my mum we broke up (we haven’t) i just want my mum to see that i’m not gonna do anything serious and trust me a bit more any ideas???