Williams released a statement saying ... "I did drink the night before the arrest. I suppose my hormones got the best of me. That was the only occasion I consumed alcohol since I found out that I'm pregnant and I really regret my decision to do so."
Williams says both she and Weston are back in rehab together -- adding, "We are not pressing charges against each other and we are working through our issues. We love each other very much."
As for the altercation, Nikki explains, "Weston and I did get physical with one another and he did not hit me in the face."
Williams concludes, "We may be passionate, but we are not crazy."