Suggest Ways To Wean Off Addiction To Diphenhydramine

how can my Daughter who is addicted to high doses off Diphenhydramine, and has been taking large doese for about 10 years, stop taking them for ever. She is 37 and a mother of a 1 year old child. She has problems with depression and suicide attempts (after she was raped) - self harmed (though not in the last year). Is under a psychiatrist and antidepressants plus other medication. Help