(Plz help ASAP) Rape accusations - true or not? - what can i do?

Im going to try and summarise what has been happening, basically two of my close friends had broken up last August after an year long relationship. However since then there has been things said by one of them that the other has raped them. However they have said that in fact she had been hurting him, pressuring him to do things as well as physically abusing him (slapping and the use of stinging nettles from what i know)

however I am very close with both of these people and none of them seem like the people who would lie ESPECIALLY about rape.

The rumours was dying down however now they are back in the spotlight, even including death treats. I really don’t know what to do, or who to believe because i dont know the finer details. Should i call someone - since rape is an EXTREMELY serious topic or should i just let them be?

Please help asap