Hi Dsh,
I didn't see your post until now, and I felt compelled to reply because I know the pain of losing someone and being unable to forget them.
Even though I am in a wonderful relationship now, it took me a long time to let go of my ex. For some reason, he touched me in a way that no one else ever has. Memories were so painful, and if I dwelled on them too much or had an association that reminded me of him, it felt like my heart was breaking all over again. I felt haunted all the time. I say all of this in past tense because I finally feel free. For me, it just took time. He tried to tempt me on several occasions, but I knew what I would have lost (my fiancee) and I would never betray him, or trade what I have with him for anyone else.
For me, it just took time. I hope you find the healing and strength to let go. I know how hard it can be.
Love,
Sujin