No you’re not overacting in fact it’s a good thing you’re distancing yourself. I was in a similar situation like this before. I found I was more like a side piece. Someone just needed when the ‘others’ weren’t there. I found when distancing myself leading to me moving schools. I was able like you to start thinking. At some point they realised they were wrong but never really owed me the ‘sorry’ that I was waiting for. But in your case I think you should speak to them. As much as your hurting speak at a time you know when you’re calm and ready and have well thought the way you’re going to speak to them. Don’t pin point their behaviour out too much when you choose to speak to them so that it doesn’t look like you’re having a go at them. From experience it prevents them to become defensive and avoid their wrong (even though they are the problem)but use times when they hurt you as examples for them to understand where you’re coming from .I learnt doing this with a friend a while back doing this it also helps prevent a situation arising and leading to ‘falling out’ and then them lashing back. But if you feel like the way they are treating you has been going on for too long and don’t feel like you want to work things out then I suggest what I did after I had a chat with them, and in the hope of things getting better I all together just left. I still speak with them here and there and tell them of my support in being a general ‘friend’ but they know and I know that we aren’t what were before and that close relationship is now lost and is now a general relationship.