Right.
Buy a fleshlight and see if you prefer it over your gf. You won't.
Anyways if you're insecure to the point of feeling these things, don't worry. Most women don't get the majority of their stimulation from the dildo, but from the vibrator. One tactic you can do is let her control the vib on her clit while you massage the g-spot and kiss her. The triple stimulation will send her over the edge in a heartbeat. An old standby position I used with my ex is laying in the spoon position, entering from behind while she used the vibrator on her clit. She would have such intense orgasms it cause me in turn to have the most intense ones of myself as her muscles would clamp down on me.
As for insertion, my ex was not much into it. Sure she would orgasm, but said multiple times she's much rather have me inside her than any toy. Ontop of that, I walked in on her using the rabbit (dildo + vib) and she was only using the vibrator part, not even inserting into herself.
So if you're insecure, avoid the dildo and go vib. Using it together I HIGHLY suggest
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