To be honest, trimming hair wont make much difference, its the health of the hair/scalp.
I cut my hair and i have really damaged hair.
I suggest the following;
Steaming your hair. I know it sounds odd but it adds moisture to your hair/scalp (Will help with both split ends and your dry scalp.
Basically, put a oil in your hair (scalp as well), use your fingertips to massage your scalp (dont rub it - that breaks hair). Wrap your head in cling film/shower cap and steam your hair. It works wonders!!
Morrocan oil is good but its dry oil. you want to start using a heavy oil (castor oi