My boyfriend feels lonely?

I'm in a long distance relationship. We're so much in love. We used to be in touch everyday, then it so happened he got stressed out,depressed and wanted to be alone. I understood that and for 4-5 weeks I kept minimum contact as he wished.(used to meet him only online for few minutes daily) Now I sense he's being very lonely and sad.. I just don't know why.. I have asked him to share it with me though he keeps silence. I'm very lonely too but I don't want to make him sadder. Am going through a hard phase in life in everything. I lookout for him then fall silent.There is no doubt he loves me and I am sure I'm a good girl friend as well as a best friend to him. I have tried everything; talking openly, trying to contact, telling my concerns, keeping distance, showing my possessiveness, supporting him. He doesn't forget to say he loves me.. Guys please suggest what should I do? When I am with him if he feels lonely, I really feel very insecure and heartbroken : ( I love him ..
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no suggestions yet : ( I must be the only girl facing something like this then.. : (
My boyfriend feels lonely?
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