No, she's the one who should have put the space--literally, like 500+ miles--between them. She should have done it as soon as she was self-supporting. Cause continuing to look at him just feeds her obsession. I'm not even sure if it's love anymore. I think she's just so into being in love with Souta that she fixates on that and doesn't let anyone else in.
I guess the mangaka wants to make this look like pure, real love. To me, it looks mental.
Oh I completely agree its unhealthy, the way it is now its not healthy.
But him just continuing to positively reinforce her obsessive behavior (what she thinks makes them close) is him not establishing any boundaries with her.
In the real world, if someone was stalking you, you'd ghost them rather then continue to give them attention. Its not all her, Souta needs to give her space too. I won't really agree with anybody that says he doesn't have a hand in this, because he DOES actually seek her out with their friends and continues to contact her. If he was serious he'd stop and try his best (if he was mature) to say they need space. Otherwise he'd just ignore her.
If Souta really doesn't like her at all, he should honestly just give her some space. #－.－)
I know Mame is the one physically going to him (he doesn't physically go to her nearly as much..) but he really needs to just speak up and say "hey we need some space for a while" or something.