The fact that he won't let you go does not mean that he loves you. There are many reasons as to why it is hard for men to let go their partner.
He is afraid you may end up finding someone who treats you better than he did. It hurts him to see someone else giving you the attention you never got from him. They are jealous of the fact you might find happiness and genuine love in another person.
You might be the one who has being more supportive to him than he was to you. In most relationships you might find one partner is more providing compared to the other one. It may be money, shelter or affection. The reason he is afraid of letting you go is the fact he knows he might not receive the same treatment you gave him from someone else.
His love for you might be genuine. Despite his past incidents with other girls, you might have come to his life and turned out to be the exact person he was looking for in a girl. Your personality, your resemblance might be everything he wanted in his girl, that's why it is hard for him to let you go. He is afraid he might not get these qualities from anyone else.
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