If you've felt quite controlled about your clothing choices by your ex then now is the time to experiment and find out what you feel best when wearing.
You don't have to just pick "glam", "frumpy" or "sensible" - you can wear different things on different occasions! When I'm not at work and it's just me and my son at home I will wear jeans and t-shirt or jumper, with trainers if we're going out, because we are usually doing DIY or something else practical and physical to take care of our animals. If I'm meeting up with a friend for dinner or drinks then I'll either wear jeans and a smart top with mid heels, or a casual dress with mid heels. If I was going on a date I'd probably wear the same. (I can't wear high heels for a variety of boring reasons.)
I wouldn't ever wear a mini skirt as I don't find them comfortable or flattering - but if you feel confident in them then you go for it!
Regarding underwear - it's remarkable how much more confident I feel if I'm wearing nice matching underwear. Doesn't have to be anything "sexy" - there are lots of pretty matching sets in Asda, Tesco, M&S, Primark, Matalan, plus more expensive options in Agent Provocateur, Bravissimo and Boux Avenue. Even though nobody can see them, it gives me a lift when I put them on and look in the mirror!
(Tip: buy one bra and 3-4 pairs of the matching knickers, then you can still wear matching sets all week whilst the first 2 pairs of knickers are in the wash
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