Raising prices for clients

I have raised my service price and am super uncomfortable. I’ve started a new client at the new price so I know it’s doable. I have an old client who wants to start again and I’m having trouble telling them the new rate. I keep thinking I should just give them the old rate and raise their rate in January when I raise the rate for existing clients. I don’t want to work at the lower rate though. But I don’t want them to change their mind and not start the service again. I don’t want to make a decision from lack mentality. I don’t understand why I can’t settle into my new rate. It’s still just as uncomfortable as when I first raised it.