Riley Strain's Mom Recalls Last Conversation They Had Before He Went Missing. It Ended with 'I Love You'

Riley Strain's parents aren’t leaving Nashville until they find their son.

“We’re searching everywhere,” mom Michelle Whiteid, 52, tells PEOPLE on Wednesday.

One thing she wishes is that she could tell her 22-year-old son, who vanished after leaving a Nashville bar on Friday March 8, is how much she loves him — another is, "we're going to find you."

“I’ve never gone this long without talking to him,” his mother says of the University of Missouri senior. “He just always wants to make sure that his mama is okay, no matter what. He’s such a great kid.”

The two usually talk several times a day, starting from when they wake up and say good morning.

“If he was having a bad day at school, he would call me and we would talk,” she says. “I’d be like, ‘You just got to get through it, Bub. Not every day is going to be perfect, but you got to find the good in everything.’ ”

The night her son went missing, Whiteid had a migraine. Still, they were texting back and forth before Strain — who was in Nashville with his Delta Chi fraternity members — went out for the night. He texted her a picture and said a buddy had let him borrow one of his shirts. “Doesn’t this look so Nashville?” he texted.

“I’m like, ‘Have so much fun,’ ” she says. He texted her a photo of him at Miranda Lambert’s Bar, and then she thinks he was at Garth Brooks' bar when he FaceTimed her with his buddies.

“I was laying down, and I didn’t want him to know I didn’t feel good, but I was just telling him that I was watching a show,” she says. He and his friends joked with her about why she was in bed so early. “They were giving me a hard time, saying, 'It’s 7:30, what are you doing in bed already? Come on, Mom, get up!' "

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“We FaceTimed for a while, he wanted me to see around, and he was so excited,” she remembers. “Then we hung up and he texted me and he was like, ‘It was kind of hard to hear you, but I wanted you to see what was happening.’ "

"I said, ‘Well, you boys be safe. Make good choices. I love you guys.’ And he said, “I love you, too,’ " she adds. "And that’s it, that’s the last I have heard from him.”

Over a week later, she has no idea what happened to him.

In an update on Tuesday, police said they are "doing everything" to find the missing student and that their investigation was ongoing. But besides a bank card that was found near a river, there's been no other physical evidence.

“I think he got turned around and just went the wrong way,” she says. “I don’t know. Everything’s speculation right now.”

She hopes to find him, take him home and make him his favorite meal: chicken parmesan.

“I want to thank everyone for searching for him and keeping him — and us — in their prayers and their thoughts,” she says. “It means so much. It’s what’s keeping us going.”