Great question.
A few tips that might be helpful:
1. Stop looking for new ideas. Instead, try look for problems/pains that people or companies have. Once you've found the pain point, then work on the solution.
2. Market research shouldn't be taking you a lot of time. At least not the initial research. It should be lean (fast) just to get a quick understanding of the market. Maybe you're spending too much time researching and not validating your assumptions? Read a bit about the Lean startup. You can also read my short article about validating your idea: https://startuplawyer.co.il/everything-you-need-to-know-about-a-privacy-policy-for-your-website-or-mobile-app/ (article will be up in a day. I'm busy updating and backing up the website).
And remember: Facebook wasn't the first social platform. Google wasn't the first search engine and Tinder wasn't the first dating app. Meaning that even if someone is doing it, doesn't mean that it still isn't something you could/should do.

Good luck!

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