Preheat oven to 350. In a large skillet over medium heat, melt butter. Add garlic and cook until fragrant, 1 minute. Whisk in flour and cook 1 minute more. Pour in milk, whisking constantly, and bring mixture to a simmer. Stir in cream cheese and Parmesan and simmer until sauce thickens, 2 to 3 minutes. Add lemon juice and parsley and season with salt and pepper.