According to a source from Us Weekly, "Pete’s mother was very nervous about his relationship with Ariana when they started dating."
This mainly had to do with the mental health issues Pete was struggling with, including his diagnosis of borderline personality disorder back in 2016.
"She knows her son goes through manic episodes and thought he was rushing into a relationship and would wind up getting hurt."
She feared that if the pair broke up, then her son would "become very, very depressed and resort to self-harm."
This comes very shortly after Pete opened up to Variety magazine about his suicidal thoughts at a very young age.
"I’ve been in and out of mental health facilities since I was 9," he said. "I tried to drown myself in the pool when I was in the fourth or fifth grade. I was trying to get my head stuck in the ladder in the deep end, so I would not be able to get up. But I’m too much of a p*ssy and my head is too small."
Thankfully, Pete's mother "has grown to love Ariana and can see how much she loves Pete."
A family insider explains, "It has gotten better now that she knows Ariana better."