I know it feels like it due to societal pressures, but you don’t have to invite anyone to your wedding, except maybe your spouse would be a good idea. Everyone else is optional.
Your mother is more important to you than your uncle, and if you want her there, not inviting your uncle is perfectly fine. In fact, I would even uninvite anyone that tries to shame you into inviting your uncle. Just additional drama that I wouldn’t need in my life.
Who comes to your wedding is your (and your spouse’s) decision only, and every invite should make your wedding better, not worse. It’s possible to be an asshole with who you invite, but in this case it’s absolutely not, you’re not trying to hurt anyone, you’re trying to prevent pain.