Devilcakes, you sound more positive this morning already!
I had to rebuild my self-esteem over the last year, and I am sooooo much happier being single now than I ever was in the relationship that knocked me down. I'd love to have someone to cuddle up to at night, too, but until I find someone who deserves me, I'd rather be on my own!
You, my lovely, are amazing. You are a loving, caring Mummy to your DCs, and you're managing your household independently. You are also clearly a positive, forward thinking person, who is looking towards a brighter future, and is prepared to do what it takes to get there. All of this is obvious from your posts, and should be real starting point to you realising how great you are.
Sometimes it feels like you aren't coping, because you're exhausted and it feels like you are barely holding it together, but you know what? It doesn't matter how well you are holding it together, what matters is that you are. Chin up, chicken, you're on your way to a fabulous future.