Coping with my daily low mood

Hello I am a 58 year old man who was diagnosed with having autism Aspergers 3 years ago.All my life I felt something was wrong with me and as a young boy this was put down to being very quiet and shy.However as the years passed by my mood level changed and as  an adult I find it very hard to be in a happy place which has brought extreme pressure on my wife and I throughout our marriage.I tend to be short tempered and very judgemental without often knowing the facts in any situation.
I have attended therapy sessions with other like minded autistic adults and because of this I know I’m not alone in the way I behave around others but it doesn’t excuse my behaviour.Even taking anti depressants daily do little to help how I feel and act,I just felt that maybe sharing my thoughts with others in a similar situation may help me in some way.