Headaches

There are times in my life where I actually thought things were going in the right direction. I really did want to believe to keep my head up and to be positive about everything. I still do....sort of. Its just hard with $300 to my name total (no savings, no 401K....) with a masters degree that does nothing for me. I've applied for thousands of jobs and feel more worthless with every direction. Thats me being honest. I am smart. I have three degrees and at most I make lives of people I work with better but underneath it all, I am still sad. My kids are honestly all that keeps me alive. I hate being the negative nelly all the time but seriously, how much can one person take. I apply for 2-10 jobs each day still because I need to get on my feet but its seemingly impossible right now. I don't understand honestly why I can't find a job that pays me at least to use my brain and I can live on my own with my kids. I am sad, defensive, annoyed all at once and am losing the courage to be strong all the time. Not sure what to do anymore.