Scared of death

I have extreme anxiety about losing my boyfriend. He is my first love and the only love I have had for the last 6 years of my life, he is the father to my angel babies and a miracle to my world. From the day I met him I have I instantly felt immense fear over the amount of love and care I have for him I knew from that day on that I never wanted to live a second without him in my life... he isn’t sick, he isn’t going anywhere but I cannot help but have a constant fear of him being gone and myself being left alone in this world without him. I always told myself if anything ever happened to him and he was to pass that I wouldn’t survive another day and I mean that quite literally, I always imagined ending my life after he was gone and to many that may seem stupid and idiotic but he is my world and he is the only thing I have had and know for the last 6 years and without him I don’t know how I could cope, the thought of a single breath without him shakes me to the core!! I have anxiety about losing him and anytime I think about it I get physically sick I get dizzy my heart beats faster than ever I get sweaty and I cannot breathe! The thought of him passing and being under ground or burned and put into a closed space makes me sick, I imagine him being scared and feeling everything and I know it’s not realistic because he won’t feel anything and he won’t know what’s going on but what if? I would hate myself... I have seriously considered counseling because sometimes the thoughts and fears become over whelming that I break down and don’t know how to take myself back to reality, I’m not asking for any advice I just needed to tell someone because anyone else would think I was crazy but I can’t hold it in any longer I don’t know how to deal with the anxiety.