I'm in a similar position, but I really let myself go while I was married. Once I started divorce proceedings I took myself in hand. So the first thing was a decent hair cut and colour. I try to maintain it, sometimes I might have to go an extra month between cut and colour if finances don't allow, but I always wash and style my hair every morning. I also always keep my eyebrows in check now.
I have an epilator so for five minutes or so every morning before I get into the shower I run it over my legs. One year hair free this week - first time in my adult life I've managed to maintain smooth legs EVER.
And I always put on makeup every morning. While I was married I was so unhappy I couldn't actually look at myself in the mirror, so never wore make up. Now I do this for me, foundation, blusher, eye shadow and mascara. Really gives me a lift for the day. I've realised I quite enjoy experimenting with different looks.
I did invest in new clothes, not too many because funds are short, but a couple of pairs of nice jeans, tops, and skirts. I don't look a scruff when I go out these days, and more importantly I don't feel dowdy. I found Gap sale was good for me.
I make sure I really cleanse my face on a night and I do a glycolic acid face peel once a week, use Australian Gold etc. My skin is looking the best it ever has.
And this week (a year post split) I started taking tennis lessons. I had a great time, got myself moving, met some really nice people who I think I could become friends with. Basically, I've got to stop hiding in the house and do something for myself. For the next 12 months, I'm going to make sure that there is more to my life than DCs and work. I'm going to do something for me.
This is something I've put together over the course of the last year and not necessarily overnight. It helps me to feel good about myself and gives me the confidence to go out and take the world by the balls. Think of one thing you want to do at a time, address it, take time to get comfortable with it and then move onto the next thing.