Police interviews - 3 weeks on....

[Bbbananas]

My friend who was dismissed from work for gross misconduct (accused of store theft; of which she is undoubtedly innocent of anything other than a silly error). The whole disciplinary was a farce & conducted wrongly from start to finish. Anyway, the police came to her house 3 weeks ago - she swears they said the words "to arrest her", but did not pursue it that day as it was father's day, and her dad's 80th birthday party - he has terminal cancer with only months to live, so they let her go. They said they would be back later that week.
3 weeks later - nothing. No phone call, no police statement, nothing. Without taking a statement, can they just drop the case & not pursue it? Is it unreasonable to keep a person anxiously waiting all this time? Is it just that the case is not priority but very likely they will come back at some point?