Cook the spaghetti according to the package instructions. Drain and set aside.
In a large skillet, heat olive oil over medium heat. Add garlic and red pepper flakes, sauté until fragrant.
Add the mussels and white wine. Cover and cook for 3-4 minutes until mussels open. Discard any that do not open.
Add shrimp, cherry tomatoes, and seafood broth. Cook until shrimp turn pink, about 3 minutes.
Stir in the cooked spaghetti, butter, and season with salt and pepper to taste.
Garnish with fresh parsley and serve with Parmesan cheese if desired.