Desperately needing some advice

So I know it's gonna sound classic but I'm asking for advice about my relationship. We've been together for a month now, but plot twist this guys been in love with me for three years and it's only a month ago that we started dating. He seems like the perfect boyfriend when he's around but as soon as he goes home I won't text him. I'll leave it cause I've seen him for a long time. But then when I do text him, he'll see my message straight away but he won't respond for hours. But if I call him we'll end up talking for at least three hours. A friend is saying that this is mental abuse. So if you've read this far please leave in the comments some advise cause I'm a little lost

Btw this is Hayden and I