history: I feel alone whenever i think about my dad.. He passed away last year. i feel alone whenever i think about my dad_comma_ he passed away last year I'm so sorry.  You have my deepest condolences. Its hard to not feel isolation with the death of someone you are close to.  I can tell you it does get better and you are not alone.  He lives on in you.
current: yeah.. i know.. memories still haunt though..
next: Take joy and pride in the memories you have of him.  They are your personal family movies in your mind.  Cherish them because not everyone gets them with their parents.  Its good to find support and counseling too if you need it. Take care of yourself.