I thought of your predicament overnight, remembering that a near identical situation arose for my cousin.
When she was about 20 and getting married, her mum (my aunt) said some incredibly nasty stuff. You wouldn’t believe.
My cousin then blanked her for the next few decades until my aunt’s...
In the short time you’ve got to decide, I’d say assess whether she was a loving and kind mum to you before the issues.
If the answer is no, don’t go. You’ll only be going out of guilt and/or family pressure.
If she had been, then probably go. You may live to regret not going.
Just my thoughts.