Scale 1-10 how big of an A$$hole is my bfs mom?!?

My boyfriends mom sent my boyfriend a text saying "can i send a picture?".. then she sent a picture of his exgf and a horse.. (hes been with me for almost 2yrs and we are planning for the whole 9 yards.. i spend holidays with his family and they all seem to like me) (he hasnt been with his ex for over 3 years.. we ran into her one time in the 3 yrs and it was an awkward hi..) BUT anyway the picture was from a graduation invitation.. and my bfs mom told my bf that she was going just so he knew and told him the date... (i think she was telling him that so they we dont visit then cuz they wont be there) BUT his mom has to drive like 1hr and a half to watch the girl graduate.. and graduations especially college graduations are no quick thing so im like seriously???? reallly???? now the next time we visit his parents i knowwww im gonna be so uncomfortable bc i cant find a logical reason that she would go to this!!! and if her text was also asking my bf if he wanted to go then she is and a$$hole no doubt but im not totally sure.. i also cant understand why the girl would invite her exbfs parents.. that makes no sense to me either unless shes tryna weasel her way back into the picture