I want to say "I love you" to my girlfriend, but I am afraid to put it in front of her.
It's awkward, but not entirely incorrect. It's another way of saying that you are afraid to say something that will force her to answer truthfully. That is, by telling her that you love her, you're putting her on the spot to tell you if she loves you in return.
Ex: I want to say "I love you" to my girlfriend, but I am afraid of putting her on the spot.[2a] What has put you in such a terrible problems?
[2b] What has put you in such a terrible mood?
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