Jamie Lynn Spears' Happiness Ruined By Boyfriend's Ex

Pretty Kelli Dawson has opened up about her feelings for her former toyboy lover - who recently became a young father - in the pages of U.S. magazine In Touch.

In an exclusive interview, sobbing Dawson claims she and Casey, 19, were still sleeping together when Jamie Lynn, now 17, was six months pregnant with his child.

And Dawson, 28, states she and her `ex' still meet up on a regular basis: "I see him all the time, at least once a week... We still have feelings for each other. I still love him and I think he loves me."

The bombshell news comes months after infidelity rumours surrounding Aldridge began.

Dawson, who grew up in Gloster, which is close to Casey's hometown of Liberty, Mississippi claims she first met the student hunk in November 2006, while he was dating actress Spears.

She tells the publication, "We were both really attracted to each other. He totally instigated it and pursued me. His friends would tell me that he liked me, that he thought I was pretty."

Despite her better judgment, Dawson fell for Aldridge, and claims their relationship became intimate in the spring of 2007.

And she expected her boyfriend to become hers exclusively as he and Spears constantly fell out.

She explains, "You never knew if they were broken up or not, because it changed from day to day!"

And Britney Spears' first husband, Jason Alexander, has confirmed Dawson's love story, insisting it has become common knowledge that Aldridge is two-timing Jamie Lynn, the mother of his child.

He adds, "Kelli and Casey have been a couple on and off for a few years. They were a really tight couple, but I think it was hard for Kelli, having Jamie Lynn in the picture."

But the big shock is perhaps Dawson's claims that she had sex with Aldridge shortly after it was announced that then-16-year-old Jamie Lynn was pregnant in December (07).

She recalls, "It happened very casually. He came by the house and I went off with him in his car and had sex."

The other woman admits the pregnancy news was "like a dagger going through my heart. It hurt so bad."

But she explains, "He (Casey) thought she was just saying she was pregnant to get him back, because, at that point, they were broken up once again. He told me it wasn't true and not to worry.

"At no point did he say, 'Kelli, she's pregnant, we can't do this anymore, it's not right.' We would hang out and hook up, have sex. I don't know where Jamie Lynn thought he was. He probably said he was just going out with the guys, but really he was coming to be with me."

Dawson claims she ended the romance earlier this year (08) because "it just didn't feel right".

She says, "He had to deal with the baby coming, and it had to stop. (But) even after we stopped having sex, we would still kiss occasionally."

She now has nothing to do with her ex, but she can't believe he's happy with Britney's little sister: "I think that he is trapped. When I see Jamie Lynn doing interviews and talking about how happy she is with Casey, it seems so fake. She's trying to paint a pretty picture, but it's messy art.

"I want the best for him (Aldridge). I would never trap him into a life with me. I would want Casey to be with me for the right reasons - because he wanted to."