I Have Anxiety Disorder With Chronic Sleep Problem. I Am

I have anxiety disorder with chronic sleep problem. I am using trazodone 100 mg and used to work great for my insomnia for several years, almost 8 years. Now it is not working. My insomnia initiates an anxiety feeling from my concern of being not able to sleep. I do not think I have any features of major depression. If I sleep well, I am in a very good mood. I have good energy level even with lack of sleep.
My doctor prescribe Brintelix for me. I am afraid that it will increase my insomnia and anxiety. I have really bad insomnia before when I tried Effexor only once. Should I avoid all SSRI and try behavioural therapy instead