Mw99 - With all honesty, yes. Here's why: If we're friends, that is we care for each other and in a romantic way, then WHY would bf say no? Unless you had a legitimate reason, that you could state cogently (such a physical problem, trauma) to indicate otherwise, I would be HURT. To be rejected in this way, by someone I (hypothetically) loves and is sexually aroused by is unrequitted love. Unrequitted love is extraordinarily hurtful!
Just by logic, I would be thinking: He cares about me, says I am attractive, we're bf/gf...yet he rejects me! Why? This does not make sense. We are at an impasse. Just try to imagine, if the situation were reversed, how would you feel (ie: Frustrated out of your mind?).
Mw99 - Why do you tell her no? Think about why...then tell her. But be ready to hear from her, "I'll find someone who DOES appreciate me - bye." I do not mean to be harsh, but you asked, I answered.
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The ones who say “You can’t” and “You won’t” are probably the ones scared that you will. - Unknown