Doubts after fiancé ‘seemed to go off sex almost overnight’

>> I recently got engaged after four years with my boyfriend. I love him to bits, but I have huge doubts because our sex life has dwindled to almost nothing. His mum died unexpectedly and he seemed to go off sex almost overnight and started drinking a lot. He is also paying off huge debts. He has had counselling for his grief. He is caring and tells me every day that he loves me, but I feel as though I will never have a fulfilling sex life if I don’t do something now.
>> You are absolutely right to try to resolve this problem now because marriage tends to exacerbate, rather than diminish, sexual difficulties.