Bf found vibrator 😩

Sooo I bought this rose vibrator a couple weeks ago and have used it a couple times before bed. Me and my bf live together so I’ve just been keeping it on my side under the bed. Well be found it today and was really upset saying how he doesn’t like how I was keeping it a secret

Which I get, but the way I look at it is he masturbates and doesn’t tell me about it (which I don’t really care) so I don’t see how me doing it is any different

I’m just embarrassed bc I was gonna tell him eventually but idk why I haven’t. What should I do?? He’s really upset