to not be homeless

I am a 59 year old widower with an 18 year old son.  We lost my wife when my son was only 18 months old,  I have needed a knee replacement since 2011. I lost my job that same year.  We have been scraping by off my 401k and savings.  I am now about 6 weeks from being totally broke.  I have applied at well over 300 jobs since 2011. Due to my needing a knee replacement I am unable to stand 8 hours a day