I've just turned 30 and my life is scaring me

Hi, first ever reddit post. I've read other people's life dilemmas many many times on here for validation/advice, and I'm at a point now where I need to ask something myself!

So I was with my ex for 10 years, aged 19-29. I thought he was the love of my life, couldn't live without him blablabla... Last year he proposed, which was THE HAPPIEST day of my life. I've never felt so high in the clouds. I was bursting with joy every day after that. I've always worn grungy/gothic clothes and I found myself wearing lots of pink, flamboyant outfits. I couldn't wait to marry him and start a family. I felt like a beautiful, happy woman and was dressing how I felt I guess. Warm, flouncy and feminine. Everything was finally coming together. My tumultuous life was approaching it's happily ever after. After that he was at the gym A LOT. Like I wouldn't see him from 5am- 11pm. 4 months later I came home and he dumped me. Out of the blue. He didn't love me anymore, he didn't want kids. He didn't want me. I later discovered he'd found another girl at the gym, and that was that. The heartbreak is indescribable, I'm still recovering now. I jumped into another relationship 2 weeks later. A man 5 years older than me with 2 kids. I was terrified that I'd never have a family and couldn't believe my luck when I found someone already with kids who would be happy to have more. We've been together a year now, and I'm realising that he's not right for me... I think I got with him out of panic and desperation more than for genuine love. He's hell bent on moving to Australia next year (we live in England) and we've been planning our big move.. and I've secretly considered not going with him and ending it. Maybe I'll give life a go on my own- I've always gone along with what my boyfriends want, for 10 years of my life. And it got me nowhere! But am I being stupid? Should I be grateful for what I've got? I'm 30 and with someone who would give me a family and a better life in Australia. He'd be earning a great wage over there as a chef, I'd have a much better wage than I do here. I could have a lovely home, children, sunshine.. Or do I stay in the UK on my own, on a teaching assistant's wage, and risk never finding anyone and never having a family? I'd finally be taking control of my life and being independent.. but at what cost?

Please tell me what you would do