[Medusa]

I'm always a little sad when folks have a breakup and I often find myself wanting to soothe the situation or help them transition into singlehood as painlessly as possible. (unless one of them has been an asshole)

I'll use Scorp and Divina as an example. I have a long-term friendship with both of them and love them both dearly. If something were to even happen between them, I would be broken-hearted on their behalf and offer my support to both of them.
However, if I found out that Scorp had gone nuts and torn up their gorgeous home and then thrown a bowl of spaghetti at Divina and then proceeded to blast her all over Facebook, I would have serious issues with Scorp and knowing that she had treated someone she loved (and that I loved) in an unforgivable way would make it hard for me to respect her or maintain a friendship with her.

I have sometimes found that when 2 people break up, one or both of them might expect "loyalty" from their friends and be irritated for spending time with their recent ex. This is a hurtful and unfair situation but I'd hope that the people breaking up would make a genuine effort not to involve their shared friends.

I'll also share a little experience I had several years ago. (not about anyone on this site)

I broke up with someone I had been having a lengthy relationship with and hoped to move forward with relative peace. Upon our break-up, someone who I considered a very close friend all of the sudden started reaching out to my ex in a super-personal way. They had never had any kind of personal relationship before and my friend had never expressed any interest in building a friendship with my ex until the day I broke up with her. This person was also in a lengthy relationship so it wasn't about her trying to date my ex or anything but it definitely damaged our friendship.

I think that as long as people are honest and in touch with their feelings and are also sensitive to what other people are going through (on both ends! The people breaking up and the people having to navigate around it!) that people can still maintain relationships around it.

As far as someone dating someone I have prior knowledge about, it depends on the level of friendship I have with them on what I tell them about the person they are about the date. If it were, say, Irishgrrl whom I have a deep friendship with, and she were about to start dating a Butch who was a known con-artist, gamer, or had substance abuse issues, I'd pick up the phone in a heartbeat.
It might go like this:
"Irish! GIRRLLL, you can NOT date that fool! She's a con-artist!"

If it were someone that I am friendly with but whom I do not have a close tie to, I might wait until they asked if I knew anything or I might say "Hey! How's it going with so and so?" Don't get me wrong, if I knew that someone was actively lying or scamming, I'd say something.

I always hope that when people get together or split up that it is with open hearts and the best intention toward the other person. <3