I'm with CoteDAzur on this.
There's a lot of knee jerk - alldrugsarebadok!! going on here when quite clearly it's not the case, 'Chasing The Scream' explains how cannabis was chosen to provide work for the US government enforcers about to lose their jobs after the repealing of alcohol prohibition and how the US government then followed this up with economic and UN voting leverage policies to persuade other countries to follow suit.
These days many countries police now turn a blind eye to personal possession. Perhaps ask Portugal, Netherlands, coming up to a third of America (and more states following in November), Switzerland and many other places why cannabis is officially legal.
It isn't a big deal, otherwise the many millions in the UK alone who have smoked it at some stage in their lives would now all be in a terrible position... It's estimated up to 30% of the UK aged 14+ have smoked at some stage. Wiki
And guess what links politicians like Andy Burnham, Harriet Harman, Yvette Cooper, BoJo, Mo Molem, Nicola Sturgeon, and other famous people like Richard Branson, Oliver Stone, Rihannah, Robert Downey, Madonna, Depp, Jolie, Brian Cranston, Pitt, Gaga, George W, Clinton and even Obama... the list goes on, and on, for ever. Yup, they've all smoked the terrible weed.
However, back to OP's question, she should make her own informed choice, she shouldn't be pressured by her bf/fb (or whatever his status is) and I hope and trust all will be well whichever answer she chooses.