Damned If I Do

Christmas has passed. I meant to post a little more frequently than I did, but oh well. The festivities were pretty much the same. Christmas Eve, my aunt, her boyfriend, and one of my cousins came over. We ate and drank and laughed and talked. I had a glass of wine with them and took part in some of the political discussion. Am I growing up? On Christmas, I was woken up early and we opened gifts. I got the newest iPod (technically a VERY late graduation gift), a domo blanket, an upgrade on my OneRepublic tickets, Newton's Cradle, fuzzy socks/booties and other small gifts. Nothing really took my breath away, but it was fun nonetheless. The day after, I went into the city with my dad and brother. It's a family tradition. We always go into the city the day after Christmas, look at the window displays, see the tree, and (most importantly) shop for discount Christmas ornaments at Lord & Taylor. We always pick up a few ornaments as a way to remember that year and our adventure into the city. It's a nice tradition, and I don't think I want to stop it any time soon. Today I visited the elderly man Mr. Caster. I brought cookies and we watched a movie. It was nice, and fun. I went home and baked a batch of oreo cheesecake squares for Bambi's family. I'm going over to his house tomorrow to exchange gifts so I figured I would bring his parents/grandparents something as well.
There's been an issue weighing on my mind. I wasn't happy about Adri and Leo dating. I wasn't happy in the least. But I spoke with Adri today and she seems to really like him. As Bambi told me, it isn't my place to tell her who she can and can't date. Adri asked for relationship advice and opinions on Leo. I gave her my help and hoped it was good enough. I thought about it for a bit, and I feel like I should reach out to him. I already wrote a draft of what I wanted to say and how I wanted to say it. Opening lines of communication could prove positive, but also negative. I'm unsure of what to do. I don't want to talk to him as a friend, but just as Adri's protector. I want to explain to him that he needs to take care of her and make sure this is something he wants to do. This is what I have so far:
Hey. I know we haven't talked in a while. I'm not coming back to fix what happened. What's done is done. It is in the past, and cannot be repaired. I just wanted to message you about Adrianna. I've caught wind of your relationship. To my surprise, and I'm sure yours as well, [Bambi] is more supportive of you two than I am. I don't think she's ready for a serious relationship, and I know what kind of mindset you must be in. The last thing I want is for her to get hurt. When I found out about your relationship with her, I was close to coming to your house and confronting you. [Bambi] actually stopped me and defended you. It isn't my place to tell her who she can and cannot date. This is true. I was talking to Adrianna just yesterday about you and her. She likes you. A lot. If you don't intend this to be a serious relationship, then stop it now. If you truly do like her, then tread lightly. I'll be watching. 
Is it too much? Is it threatening? I don't want to sound hostile. The last thing anyone wants is for shit to be stirred up. I have 3 options. 1) Send this message, and hope he listens. 2) Tell him to meet me in person so we can talk and figure it out face to face. 3) Not do anything and stay away from the situation. I'm not sure what I need to do. I'm damned if I do, and damned if I don't.