Dreams about his ex?

I've been with my fiance for 3 years. He was with his last long term gf before me for almost 9 years. Ever since we started dating and I learned who she was, I've had dreams about her.. I always feel off the whole day after I have the dream. But this one was different. In all my dreams before he's my boyfriend but she acts more like he's hers and I was never mad or jealous in the dream because he seemed not to even acknowledge she was there. I had one that I was in the back seat of my car and he was in the passenger seat with her on his lap. Now, they ended very badly, restraining orders and she tried to have him killed. She even egged my car and was very childish about him moving on so I know he's not cheating on me with her. But last night in my dream, we were all in high school together. Which was odd because they're both 6 years older than me. Anyway, she was my friend in the dream and I was dating him. But in this one, he actually acted like MY boyfriend. He was kissing and spinning me around and ignoring her. She would tell me how he did it with her too and it didnt make me feel jealous. I felt bad for her, in my dream, because she seemed jealous. Now mind you, I've only met her a few times. One of those times I confronted her about egging my car. So none of our interactions were friendly.

Anybody have an opinion on this?

When I was with my ex husband I used to have dreams he was cheating on me, and a couple days later, I found out he was. I also have an older brother that died in 2014 and I've dreamt about him only a few times since he died but every time I did, something terrible happened that week. As crazy as this sounds, I feel like some of my dreams actually mean something.

My fiance started doing pills with this girl when he was 14. She was stealing her moms and taking them and got him doing it with her when they started dating. He almost left her over it but was in love so he didn't. He's had a drug problem since then. He's struggled with it since we've been together and I've supported him through it. The last couple months he's been the most determined to get over it than he has the whole time. I feel like those dreams had to do with it. In my own opinion, she represented the drug problem. Him not acknowledging her represents him not feeling like it's a real problem. And him actually being mine in this dream makes me wonder, maybe it's actually over. Or another theory is, we are VERY close. So maybe those dreams were me connecting to the fact that maybe he's not fully over it subconsciously. And maybe that dream was him finally subconsciously letting go?

Idk, either way, I really feel like some of my dreams actually have real life meaning. like the cheating dreams with my ex, and my brother visiting me and telling me everything would be okay before I even knew anything was wrong.