Slow Cooker Church Supper Spaghetti

2 pounds ground beef
1 large onion, chopped
4 cloves garlic, minced
2 cans (28 ounces each) crushed tomatoes
1 can (15 ounces) tomato sauce
1 can (6 ounces) tomato paste
1/2 cup red wine (optional)
1 tablespoon sugar
2 teaspoons dried basil
2 teaspoons dried oregano
1 teaspoon dried parsley
1/2 teaspoon crushed red pepper flakes
Salt and pepper to taste
1 pound spaghetti