White guilt isn't a useful tool!!! White guilt and shame make racism about white people and their poor feelings. I'm over it. I am over the "white ally" conversations about feeling scared to say the wrong thing, feeling guilty for not knowing better sooner, feeling heartbreak and pity for black folks. Your feelings don't create action. Wallowing and crying over "what if I mess up?" doesn't help anyone.
Get over it. Accept that you've messed up and offer reparations if possible. Embrace the fact that you will continue to mess up because every white person is racist. Fuck it up, get shamed, apologize, and change the behavior. That's how we teach children, is it not? Do we let children sit and wallow in shame? No. We say, "it's okay to make mistakes, here's how to make it better, don't do it again" and then offer consequences, and we rinse and repeat until it sticks.
Allies who are stuck in their white guilt always say "I don't know where to start, what do I do?" But it takes a single google search of "how to be anti-racist" to find whole long lists of ways to help and change. Sitting in groups of white people and harping on feelings of guilt isn't on that list. If you're not willing to step up and do take action, then why bother?