@ Snowbunny – May I point out is that many people do NOT eat chalav yisrael, despite the comments above.
There is no such thing as ‘not kosher’ milk that you can drink. If something isn’t kosher you can’t drink it. There is non chalav yisrael milk that you can drink, and it has an ou and is 100% kosher.
If you are unsure if you should be following a CHUMRA or not (yes, it is a chumra), ask your Rabbi.
In a general sense (Stating my opinion here) If you are going to ask practical questions on this forum, and taking the answers at face value you will be taking on an awful lot of chumrot that are presented here as obligations. Better to be informed.
To juxtapose another thread here – I will opine that a great contributor to OTD-ism is precisely the attitude expressed above. Non-chalav yisrael = non kosher. Therefore if i eat a Hershey bar i may as well go have a blt.
This is messed up, people.