Heat the olive oil in a large skillet over medium-low heat; cook and stir the garlic, bell pepper, and red pepper flakes in the oil about 20 minutes. Dredge the shrimp in the flour to coat, then shake off the excess. Raise heat to medium-high and stir in the shrimp and tomato; cook until the shrimp is pink, 3 to 5 minutes. Add the lemon juice, wine, and butter; continue cooking until the sauce thickens, about 5 minutes more. Garnish with parsley to serve.
