How can I talk to my new man about money?

I'm a divorced woman in my 40s and have had to get used to a big change in lifestyle.

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I downsized to a small place with my three kids after we sold the family home and I don't have a lot of spare cash. I do work, but only part-time, in order to be there for the kids, so I'm not earning much.

My ex has his own business and is successful, so I was used to a certain lifestyle - big house, nice car and money for holidays, clothes, and a great social life.

My dilemma is, I've been dating this man I met through an app, who's a dream, but I can't compete with him in terms of income to do things. I'd find it embarrassing to say I can't afford to go out with him and I don't want to ask him to pay for me, so I often turn him down when he invites me out.