I struggle with that too, minus the spending aspect.

Get your girl a solid set of ad- blocking tools, including alternative apps without the ads or simply the mobile websites. Set up pihole, an ad blocking DNS, that sort of thing.

Try RSS. Feedly is good for this. Try old.reddit.com, after removing all the nasty subreddits from r/all. Try newsletters.

Filter emails, unsubscribe from newsletters, turn off notifications. Basically, pay attention to the triggers and shut them down. She will still seek cheap dopamine, but it won't be laced with ads. Nothing will reach for her attention unless she asks for it.

I described the exact steps I've used to fight that problem here: https://nicolasbouliane.com/blog/silence - it's an ongoing process. Reading your post makes me realize that I've made a ton of progress.