People who are rising to the top will have smear campaigns launched against them from people who are negative and also from people who are highly jealous or people who have to be the center of attention. They can't stand it when someone else is getting the attention.
You wonder what you have done to cause this. You have probably done nothing but better your life. There will be people who have waited 5, 10, 15, 20 or however many years to strike against you. You could have lost touch with them and because of social media they have located you. They act friendly and want to become your best friend. Without warning, they strike because in their minds an event happened a certain way. If you remember what happened at all, you don't remember it the way they did. They can also be taking out on you what your spouse did and they hold you responsible for not sticking up for them instead of your spouse or a significant other. Over time, the mind adds things to an event - things that didn't happen. The person will swear up and down it did happen.There's nothing you can do about it except go forward - go on with your life after you stop communicating with these type of people. They will keep striking until they find that you have taken the high road and ignoring them. If you think about it, it's pretty sad that these people don't have anything better to do in their life except to strike out at others. As the quote goes, "hurting people hurt people". They are hurting for whatever reason that has nothing to do with you. The events that turned them into who they are have to do with how they were raised. They were most likely brought up in a highly abusive environment. They have made it their life mission to rid the planet of anyone who hurts them or take it out on someone else.
If you're in the process of rising higher with your life, business, career or all of what I mentioned, learn resilience Don't focus on these negative toxic naysayers = stay focused on what you're doing and your goal. The naysayers will always be there and if you can't handle the lightning strikes, you won't last - you won't make it as your mind will be too focused on someone tearing you down than what you need to be focused on. The strikes may hurt - learn to bounce back and not take any retaliation against the naysayer or you will be expending all of your energy on that instead of what you should be spending it on.
Keep going forward and higher with love, grace and fortitude.