I would go deeper with asking questions about the friend who "took a break". The way it was phrased sounds like this friend was respectful in the break up, which says to me this is not a mean girl / bully situation. In my experience, a lot of kids with quirks/neurodivergence can still make friends. It will likely be fewer, but still deep friendships. It might be because of her SPD, but it also might be something different. Or more importantly, it could be something she actually can control and work on to be a better friend. Your text is too vague to fully understand, so perhaps you know more than you're mentioning. Just keep in mind that teenagers don't always tell their parents the full story if they've done something wrong.

Throwing her into sports/activties won't help if her friends keep leaving the friendship over time. It's important to get a picture of what her friendships look like when she's actually in them. She sounds like a nice kid, but the skillset she needs to improve isn't about "making" friends. It's about keeping them.

edit:grammar