Definitely get your eyelashes dyed if they are fair.
I've just started doing this and it's changed my life. I look half decent without makeup for the first time ever.
The other thing is, do your hair in the evenings. You have more time to play with it and make it nice than in the mornings.Then just brush it/run straighteners through it when you get up.
Find out which colours suit you (colour me beautiful has a website that tells you what season you are) and even if you just buy a scarf/pashmina in that colour you can whack it on and look like you've made an effort.
Clarin's beauty flash balm and benefit boing concealer. The pink eye highlighter is good too. A bit of blusher and lipgloss, bob's your uncle. Keep a lipgloss in the car so you can put it on at traffic lights.
Costume jewellery and cardigans in bright colours. Get a few white tshirts, some bright cardies and you'll always have something to throw on with jeans.
And if it's any consolation, I'm 5ft 7 and trying to get back down to your weight. You are about a stone lighter than me and I don't feel particularly huge as a size 12-14.
A bit of perfume makes you feel good, too.
You just need to love yourself a bit