Tamra Wade struggled mightily over whether to go to the police more than a decade ago, when, she says, a trusted professor forced himself on her in an empty classroom.

Ultimately, she couldn't bring herself to do it.

But if it happened now, she says, she'd be a lot bolder -- not just because she's older, but because she feels there's less of a stigma connected to being a victim of sexual assault.

And this, say advocates for sexual assault victims, may be one reason the allegations against Bill Cosby have exploded into public consciousness now so much more than they did when they emerged a decade ago: an evolving cultural understanding of the crime of sexual assault, and increased empathy toward those claiming to be victims.

"I think our society really has changed," said Wade, a data analyst who now mentors young assault victims. "Ten years ago, it was much harder for a victim to get an audience listening to her. Now there's less of a stigma, and that gives people more confidence to come forward."

A key element in the cultural shift, said some advocates, has been a series of high-profile cases such as the Penn State molestation scandal, stories of abuse in the military or the Catholic Church and cases of date rape at university campuses. Particularly when a number of people come forward, it's harder for the public to ignore, they said.

"People may have an easy time rationalizing away only one victim, but not when there are a number of them," said Scott Berkowitz, president of Rape, Abuse & Incest National Network in Washington, D.C.

In recent weeks, at least seven women have publicly accused the 77-year-old Cosby of sexual assault years ago. Cosby has not been charged in connection with any of the allegations. Only one woman has filed suit -- Andrea Constand, who sued in 2005 and settled for an undisclosed amount before the case went to trial.

Cosby's attorney, Martin Singer, has discredited some of the allegations and denied others. He suggested in a Friday statement that Cosby's accusers may have another agenda.

"There has never been a shortage of lawyers willing to represent people with claims against rich, powerful men, so it makes no sense that not one of these new women who just came forward for the first time now ever asserted a legal claim back at the time they allege they had been sexually assaulted," he said.

Berkowitz, of RAINN, recalled when his organization, back in 1994, approached TV networks to air public service announcements for its sex-assault hotline; they resisted, he said, fearing the mere word "rape" would lead to complaints. Finally NBC agreed, and there were no complaints, Berkowitz said -- in fact, there were thank-yous. Other networks followed suit.

"In the last decade, we've all been developing a greater awareness of just how common these crimes are," Berkowitz said.

Recent media coverage of the widening allegations against Cosby led to what RAINN said was a "significant increase" in calls to its National Sexual Assault Hotline -- something that also happened after the Penn State case. But there's been a measurable increase underway for several years, said Jen Marsh, who oversees the hotline, which includes a phone and online version.

"Our online hotline has seen a 25 percent increase every year," said Marsh, vice president of victims services at RAINN. "I think it has a lot to do with the dialogue happening around this issue."

She, too, cited high-profile cases -- such as the 2012 rape scandal involving high school football players in Steubenville, Ohio -- and the fact students on college campuses have been more vocal about their experiences.

"There is definitely a sea change of sorts with these activists being very open," she said, also citing attention to the issue from Congress and from the White House, which recently launched "It's On Us," a public awareness campaign about campus sexual assault.

"The focus has been unprecedented," Marsh said. "We're seeing some overwhelming support."

But at the same time, she noted, it remains exceedingly difficult to report a sexual assault, "particularly if the perpetrator is well-known, or powerful, or well-liked, whether it's a principal in a local community or a famous football coach."

Marsh said that often -- as has been the case with some of the Cosby accusers -- people delay reporting assaults: "They try to get on with their lives, and sometimes it's not until later that they realize they need to do something."

Sometimes it's too late. When Wade, now 44 and living in Phoenix, went to police 10 years later, she was told the type of contact she alleged would constitute sexual assault -- she hadn't known that, she says -- but the statute of limitations had passed. (Such statutes vary from state to state.)

Of every 100 rapes, only 40 get reported to police, RAINN said, citing Justice Department figures. Eight of those get prosecuted, and four lead to a felony conviction. The silver lining is over the last 15 years or so, reporting rates have risen by a third. Some states also have lengthened or abolished statutes of limitations on prosecuting rape, especially when DNA evidence exists.

Christa Hayburn waited two years to report her alleged assault. It was complicated by the fact she was a police officer, and the man she was accusing of sexual assault was her superior -- someone she looked up to and viewed as a friend. She described an evening celebration with colleagues that led to the man allegedly forcing her into sexual activity in his car in the parking lot.

Hayburn, who was married with two children, complained to her superiors, and when the case got to the district attorney, the decision was made not to prosecute.

"I was told that I didn't say 'No' enough," Hayburn said.

The experience left her with the feeling "it was already preconceived that I was a liar." After six years, she was fired from the force; she now is a life coach.

Both Hayburn and Wade said they felt paralyzed, at the time, by the fact the men they accuse of assault were mentor figures.

"Even while it was happening, I was trying to fathom that it was happening with someone I respected and trusted," Wade said, seeing the parallels with some of Cosby's accusers who have said they were young, impressionable, ambitious and cowed by the entertainer's power and star status.

Though she said in 10 years, she's seen "great improvement," Wade added: "The reality is we have a long, long way to go before victims will feel comfortable telling and getting help."

As for Hayburn, she acknowledged she sees "more awareness out there now, and the victim-blaming isn't possibly what it was."

But she, too, said it's so difficult to come forward, she's not sure she would have any more courage now than she did then.

But she also feels it's crucial to speak out.

"If nobody is out there sharing their story, how are we going to help the next one?" she said. "That's why I'm speaking to you."