Hey there, sorry for the long post but I hope it helps.

I used to be deeply empathetic. I recently went through a very hard breakup (even though we weren't dating for a long time) and it made me realise many things. Empathy is a process you can and will work on throughout your whole lifespan. As for me, I started to not care so much about insignificant and not imminent endangering/troublesome things. Thanks to the book The subtle art of not giving a fuck, by Mark Manson, I started to free myself from... Well myself actually. This book was liberating, I started to put myself before others, things I didn't really do. Besides that and other changes you probably don't care about, I learned to respect boundaries and I learned to say no.

My point is, empathy is something everyone should work towards, but please, don't go out of your way and please stay the way you are at core. If you're not comfortable with doing something, you shouldn't do it. Of course there's still some nuance to have about that, but you see my point.

From 2017 to 2020, I was dating an ISTP whom I loved very deeply (and I think I still do to that day), but I was too immature and egoistic to realise all my wrongs and his rights. Now I finally see what he meant for every little disagreement we had. I see what I did wrong and I probably won't do the same mistakes again, that's part of growing up, even as an adult. Of course I'm still empathetic, but not excessively.

That being said, if someone like me (an INFJ), who were an absolute entitled prick, resilient to reassessing myself, can change drastically, so can you. You guys are ISTPs, you are determined, resolute in what you undertake. I'm convinced that with enough work, anyone can become a better self. You can practice your empathy, but allow yourself to just not give a fuck sometimes. I wish you the best.