I have to agree that what is happening is probably a combination of high charisma (as already noted to the OP on a different thread recently), charisma-like LTRs, and then the base game, and SP all trying to be "helpful." And sometimes it really is helpful such as when a sim is new in town, other times it's not realistic. As @IreneSwift points out, there are some ways to help soften the effects but the game is what it is and it wants our sims to have some acquaintances -- the immediate jump to Friends, which reflects a relationship score at or above +40 on the scale from -100 to +100, would be very unusual for a sim with low to no charisma (Good Friend and Best Friend require higher scores each).
What most of us see is yes, the Seasons patch initial attraction message which is often random and silly, and the sim lands on the relationship panel, but with a relationship score of something much closer to 0 or maybe +1 or +2. That's not a Friend, that is an acquaintance. If you have the NRaas RelationshipPanel mod in play, you can zap those sims off the panel and zero out any unwanted relationship scores with a single ctrl-click each. The mod also lets you see the actual numeric relationship score by hovering the mouse over the sim in the panel.
The Seasons patch initial attraction nonsense can also be modded out, I believe it's Shimrod who has a mod that can do that at The Sims Asylum, but that won't necessarily stop the game from "helpfully" forming those initial acquaintance relationships anyway.
@cody6268 - This is TS3. Sentiments are a feature of TS4. :)
