'Teen Mom' Jenelle Evans Engaged (PHOTO)

"Teen Mom" Jenelle Evans has announced her engagement to boyfriend Gary Head through her Twitter account. The news comes at a time when Evans has been working to improve her life and gain back custody of her son, Jace.

"I'm the luckiest girl in the world to have Gary Head in my life," Evans tweeted. Her message was accompanied by a photo of her wearing the new engagement ring, which was purchased at Reeds Jewelers. The couple has been together since January, when Evans began tweeting about their relationship.

She was previously with Kieffer Delp, but that relationship was shrouded in controversy especially as Evans got into trouble with the law for drug use. The two constantly fought and Delp was eventually sent to jail for crimes related to drugs. When photos of a nude Evans post-surgery surfaced, it was revealed that Delp was behind them. He allegedly sold the photos in order to help raise bail money.

Head is an enlisted United States Marine, which should provide some stability for Evans as she continues on a positive streak in her life. She was recently given release from parole and has talked with her lawyer about seeking to gain custody of her son, Jace, who has been in the care of Evans' mother, Barbara.

Evans became famous with the premiere of MTV's reality series "16 & Pregnant," then followed that up with "Teen Mom 2." The series wrapped up its third season, and all four girls on the show have signed on for at least one more season. "Teen Mom" will air its fourth and final season this summer, bringing a close to one of the channel's most popular series.

According to one source, Evans' engagement will be aired as part of the new season of "Teen Mom 2." As for Evans, it is clear that she is incredibly happy right now, which is refreshing for the troubled star.