Title fits me perfectly quite sad isn't it.

Been depressed since I was 16, to make a long story short I have no friends, no family, a fiancee and a son who I love dearly.
I never wanted kids.. hell I didn't even want a fiancee/girlfriend.. been stepped on, and beat down my whole life but it happened.
Anyway I am useless, I feel useless everyday I wake up I'm so tired.. so lost and I just wish I could vanish.. my fiancee trys her best we rarely fight.. tho I just keep thinking she's with me cause we have a son together and she keeps telling me how stupid I am and she loves me.. but as always my depression and self worth doesn't allow that. 
I work 6 days a week but I feel it's never enough.. I can't quit due to how guilty I feel about the owner.. I feel guilty for never being home.. I just need someone who understands.. anyone I talk to acts like they do but they don't.. I guess I'm just alone.. at least I feel like I am.