26 y/o male newbie here

I am 26 year old working in a private job of 8.30 to 6. I was single for almost 25 years and was not addicted to any pornography or masturbation. I usually did it once in a week and was contented with life. But then last year, a girl came in my life (i have known here from last 4 years and were just friends). We were in a relationship for about 4 months. We had kissed each other multiple times but were never involved in any other sexual activity, not even touched any physical parts. When she was with me, i never had any thoughts of masturbation. Due to some reason, which i also don't know till date, she decided to move on and don't want to have any relationship with me. My life came shattering down and i entered the depression zone. Its almost one year since she left and its still hard for me to move on. The main problem is after she left, i became addicted to more pornographic content and masturbation with the frequency of once/day. I think and try everyday that i won't watch any sexual content but urge gets over me and i ends up watching and masturbating. It has started to effect my health and my work life also. Along with my job, i am trying to concentrate on studies for some exam. But i am having problems in my studies also. Not able to focus on any thing. Seeking help from you guys.