It was reported last week that Reid's fiancé Chantelle Houghton had been left devastated after discovering private communication between him and Amy Willerton.
However, speaking to New magazine, Reid said that they had only exchanged one message - and insisted that he had not been aware of who he was replying to at the time.
The initial message from Willerton - who left Price's Black Sheep Management earlier this month - read: "Congrats to you Chantelle and hopefully i will get to meet you guys one day x", to which Reid replied: "Hope so x."
He said: "I shouldn't have done it and I regret doing it, but I didn't realise it was Amy Willerton. I get about 20 private messages a day, and I go through them and respond to as many as I can. I thought that it was harmless. Now I'm being portrayed as a cheat, which really upsets me and the gorgeous girl that I'm committed to and love with all my heart."
Explaining that he had followed Willerton after hearing of her split from Price's company, Reid said: "Obviously, we have something in common. I was promised lots of things that didn't happen [when he was married to Price]. I found it interesting how [Amy's] management treated her. Even though I'm so far removed now, I still find it fascinating. I was intrigued."
Asked if he thought she had followed him to annoy his ex-wife, he said: "I did ask myself that question, but I don't think Katie gives a s**t. How did it get out there? That's what I don't get. It makes you question people. I have nothing to gain. It's caused nothing but misery and stress for my pregnant fiancée. I should have been more savvy."
The 36-year-old said that he should have been "more responsible", telling the magazine that he does not want "any links" to Price.
"It's not nice, as you can imagine. It wasn't nice for me," he said. "She's the victim and I'm the evil one. You've got that feeling of being ridiculed and it's not nice, knowing what everyone's saying about you. I feel wrongly accused of being a dirtbag. She told me I'm a prat for contacting [Amy]. And she's got a point.
"I'd done nothing wrong, so I was sticking to my guns. That was the unpleasantness. Then I was like, 'You're right, I shouldn't have done it'. I have to remember I'm not just normal Alex Reid, I'm Alex Reid who is sometimes a celebrity."
Earlier today, Reid and Price were granted a divorce by the High Court, over a year after they split up.
> Chantelle Houghton reveals childbirth fears