You deceive me; in a lady's mouth, one would imagine, signifies, “I know you deceive me”, and only means to exact assurances to the contrary.
You say you love me, but I do not know how to trust you; I am afraid you deceive me. This is as much as to say, “I believe you but too much: but it is the custom, in such cases, to make objections: a conquest would appear too easy without them: let me have then some ardent protestations: turn my head: deceive me. I desire no better. I do not want to examine too scrupulously into the credit due to you: I wish your sincerity too much to plague myself with the doubt of it: all I want is the excuse of your vows and assurances, if but for form-sake.”
There are two powerful reasons for this interpretation.