I used to be like that. It honestly requires a lot of discipline to get out of that deep hole. It's not bad or good, it just 'is'. At least I didn't view it as a bad thing when I was experiencing it. I just wanted something different for myself.
I worked on it by creating an 'ideal' version of me in my head. If I could be anything and anyone I wanted, how would I act? Well, the first thing I thought of was "Well, he would be educated." "He would be disciplined." "He would be someone who was okay with being by himself." "He would be higher in emotional intelligence." And so on. I picked a goal out of the list of traits I desired in myself and I worked on them.
I'm proud of the man I've become. Not because I've achieved anything in particular, but because this version only exists in a world where I cared enough to change.