Masturbation questions😏

Penny
Okay... I've never been able to cum on my own. When me and my boyfriend have sex, I always cum when he goes down on me, and also when I'm on top. It feels amazing! But when I'm masturbating, I can't orgasm and I can never find a comfortable position for myself.... Might sound weird idk. Any tips or suggestions?
Also, I've thought about getting a vibrator/dildo... But I brought the idea up to my boyfriend and he got upset because he feels like he's not good enough if I have to go out and buy toys. I tried to explain to him that he's more than enough but when I'm alone, I'd want to have a little fun too. Does that make sense?