Is it normal that i don't get a boner when grinding or freaking with a girl

This is pretty normal. I've thought long and hard about what arouses me and I noticed I don't actually get excited if I don't anticipate any chance of being called to action. Never once had a problem performing, but it made me realize that paying attention to your body is important. Maybe it'll help you? Approach it like a scientist.

Well, there's a handful of different approaches to this situation, all of which are essentially totally normal.
1. You may not get a boner then, but eventually get one anyways. Some people just don't like certain sensations or touch.
2. You may not get a boner then, or at any time. Many men experience erectile issues, and while it's normal, you should speak with a doctor about it.
3. You may not get a boner because maybe you don't find women attractive ! Have you explored your sexuality ? Maybe a guy could provide a better experience for you.

Well, if you get one eventually it's fine. You might just be less sensitive to that kind of thing. Only if you can't get hard even if you're feeling in the mood you should look for the causes.
If you'd like to get more sensitive the easiest way is lowering your porn consumption and masturbating less.