HELP ><, sticky situaiton Options

[jue]

alrights so this is how it goes ><

So one of my best friends that i've known since i was like 5, lets call her "Wilma." She's going out with one of my other close friends. Lets call him "Big Will." They've been going out for almost a month. Their one month anniversary is this coming monday. Now, Big Will, he doesn't feel the same way about her anymore and wants to break up with her. We we're talking about it today in lunch. But Wilma, she's not in my lunch period, and it was a surprise when she came to our lunch. While she was sitting with us, her and Big Will didn't say a word to each other. Things went on normally. And when the end of the day came and we were walking home, Wilma comes up to me, and my other 2 best friends. Lets call them "Penny" and "Winnie" She askes us what was going on and what Big Will said cause she saw him talking about something to us. Big Will had told all 3 of us to not say a word or else he'll never talk to us ever again and he'll be upset with us. So us three, not knowing what to say, just made up an excuse and said that he told us that he was gay >_>. Unfortuntley Wilma didn't believe us. As the day went on, she would keep asking and the more she asked the more guiltier we started feeling. Soon she gave up asking and just stayed silent. While walking and everything she would just stay to the back and not say anything. We figure out that she was a bit upset for us not telling her. So the problem is, I dont know what to do. Should i tell her, so she wouldn't be upset. Cause when Big Will does break up with her, I don't want to be just standing there and have her look at me. Nor do i want her to be hurt. But the thing is, if we told her of what Big Will is thinking, I feel like Big Will would loose his trust in us cause he told us not to tell her.

So, what would you guys do? Any Suggestions? Please&thankyou.