I need some advice please please please

So me and my boyfriend have been dating for going on 6 months now I'm 19 he is 26 about two years ago going on three years August 6 his mom passed away lately he has been really sad and not sleeping I know the reason why so I understand today we were talking about it and I let him know that I'm here for him if he needs me but he told me no offense but there is nothing you can say to help me

.. I feel super sad because I just want to be there and support him and want him to know I'm here any advice as to how I can be there and let him know I'm here for him. HELP please