BAGRAM, AFGHANISTAN—Hailed as a monumental step toward equality by gay rights activists, hundreds of Dear John letters reportedly began reaching newly outed troops overseas this week, notifying soldiers for the first time ever that their same-sex partners back home were leaving them and starting a new life with someone else.

One of the many historic letters U.S. service members across the world are beginning to receive.

According to Pentagon observers, the torrent of brusque, callous letters—which followed Tuesday's repeal of the Don't Ask, Don't Tell policy—has left romantically betrayed homosexuals in every branch of the service grappling with feelings of rejection and despair, a momentous milestone in U.S. military history.

"For too long, gays and lesbians in the armed forces were barred from receiving such letters, leaving them woefully unaware that the person they once called their soul mate had been cheating on them throughout their deployment," said Clarence Navarro of the Human Rights Campaign, an LGBT advocacy group. "But now all troops, regardless of their sexual orientation, are free to have their entire lives ripped out from underneath them in a single short note."

"This is a great day for homosexuals," Navarro added. "Even those who now have nothing to return home to."

Navarro told reporters the Defense Department's willingness to embrace gay soldiers, including those suddenly plunged into gut- wrenching heartache in an unforgiving war zone 8,000 miles from home, was a sign the American military had finally moved into the 21st century.

A U.S. soldier finally experiencing what it's like to be emotionally destroyed in an 800-word note.

When contacted for comment, many troops who had received their first-ever gay or lesbian Dear John letters during mail call Tuesday acknowledged the historic significance of their crushing, coldhearted abandonment.

"This is what we've waited so long for," 1st Lt. Jared Tomasino said haltingly as he placed a photograph of his former partner—which he had just been able to tack up that morning without fear of discharge—facedown in his footlocker. "My boyfriend wrote that he didn't love me anymore, that he wasn't sure he ever really had, and that he never wanted to see me again. Those are words earlier generations of gay soldiers never had the opportunity to read. Frankly, I never thought I'd read them, either."

"It's an overwhelming feeling," Tomasino added. "I—I'm sorry, could you leave me alone now? This is a really difficult time for me."

In a statement, Pentagon officials confirmed the correspondence had caused no disruptions to planned missions, despite many service members having been informed their same-sex lover had moved out, taken custody of their adopted child, and begun a torrid sexual relationship with a close friend whom they had once trusted.

However, many in Washington remained opposed to the policy change, with Sen. John McCain (R-AZ) claiming the influx of Dear John letters would weaken unit morale and preparedness. A longtime proponent of Don't Ask, Don't Tell, McCain stated he would personally feel uncomfortable knowing that "one of the guys next to [him] in the trenches" was not only gay, but also "heartbroken, vulnerable, and looking for comfort from his fellow troops."

"There's no place for homosexuals breaking up with one another via letter in the U.S. military," McCain said. "Allowing so many utterly lonely, dejected, and newly single troops to serve on the front lines would only impair our combat capabilities and place our nation at risk."

Added McCain, "We all know how messy things can get on the rebound."

Given recent casualty figures, LGBT groups said they were also well on their way toward achieving parity in the number of openly gay military widows and widowers.