Hello all, I'm new

Hey everyone, I am new to this site. I am not a lucid dreamer or anything, and most of my dreams I have are very crazy, and after I wake up, can definitely tell that they were a dream. I found this site, hoping I could get an interpretation of this dream I had last night. Here it is, if you would like any more details, I will try to remember them

I woke up in my bedroom to some dogs playing. One being my girlfriends dog, one being my girlfriend's roommate's dog, and the last just a random dog. I walked into our living room to see my family and my girlfriend's roommate, not the roommate who owned the dog I saw, and the way it was made out was that I was dating her. I was confused because of how much I love my real-life girlfriend, she is my bestfriend.That and I do not find her roommate attractive at all, nor do I think I would ever date her. After a little while my real-life girlfriend walked in the back door of our house, and she and I walked back to my room and began making out. So my dream was basically I am dating my real-life girlfriend's roommate, but I am cheating on her with my real-life girlfriend.

The real reason I am baffled is 1) I usually don't have dreams like this that seem so real and nothing crazy happening, and 2) Why would I dream about cheating on a random girl with my real-life girlfriend? I could see cheating on my girlfriend with someone else as something I could comprehend, but not this way. Thanks in advanced for any help!