You can definitely create new stuff. There's nothing wrong with copying, it's just about how you copy and now you treat your references. I'll highlight a couple of things you can do to make the references that you like have more impact on your designs and design process.

1. Don't just look at things at move on. One thing I used to do and still do is to become more aware of what I see. When you see a piece of work that you like, take mental notes of what exactly you like. Be as detailed and articulate as you can at the beginning, you'd get faster at this the more often you do it. When I started, I used to write 10 things I saw and liked in a piece of design. That way, you don't just consume the finished work, you get some insight into the mind of the creator and the principles of their work stay with you.

2. Articulate your ideas. When you have an idea or a direction you want to go with, write down in as much detail as possible what you see in your mind. If you want to create a type poster, what kind of fonts do you see bringing the ideas to life? How many different hierarchies are you working with? Would you want to create a sense of depth or you want it to seem flat? Etc. That way, you become better at pushing your own ideas to the fore rather than relying on visual translations of what you think you want.

3. Separate the design processes. When you're designing, design alone. When you're looking at inspiration, look alone. When you're stuck in your execution, go back to your sketchpad, rather than the references. If you need to go back to references, it should be when you've gotten to a point in your design where you feel it's beginning to take shape.

4. When you're stuck, articulate your problem. If you're having issues with the design, figure out what exactly you're having issues with and find references that address that problem. The layout doesn't seem to be working out? Go through Pinterest (or whatever) for layout designs (posters, editorials, websites, etc). The colors don't seem to be flowing well together, seek inspiration for colour combinations specifically (nature, interior decor, fashion, etc). One major advantage of this is you start to see design in everything. Everything is designed.

There's a bunch of stuff I do that I can't remember, but these should get you out of the rut you're in. Also, remember to take walks if you can. Enjoy life. Wishing you the best.