Feeling Alone

How can some one feel so alone in their life when they have people in their life's? I have a wonderful family, but at times I feel so alone I wake up and don't feel good take my med's feel sleepy no one understands and I start to feel so alone. If this is the life I was meant to live I'm not looking forward to it I want to feel alive ,but don't know how ! I don't want anyone to feel sorry for me I just want to fell good all the time ok most of the time is that to much to ask? I just feel alone that's all and I don't alway's feel this way ,but this week has been a bad one for me. I hope it get's better!