''And verily! In the cattle, there is a lesson for you. We give you to drink of that which is in their bellies, from between excretions and blood, pure milk; palatable to the drinkers'' (16:66).
He even describes milk as a "healing":
There emerges from their bellies a drink, varying in colours, in which there is healing for people. Indeed in that is a sign for a people who give thought. (16;69)
What about Qurbani every year? Do you also prescribe that as a "sick practice"? Therefore my sister we should not talk from our desires. It is your prerogative if you do not want to eat meat nor consume dairy, but to call a Sunnah practice "sick" and something that "should not be halal" is completely condemnable.
So please do not take such an "extremist vegan" approach and understand that as Muslims we have the choice of what we want to eat and drink of the permissible foods and drinks, but we cannot reject or condemn others for consuming that which is a Sunnah. However we can advise others to avoid "over consumption" of meat and to eat a healthy balanced diet mainly consisting of vegetables.
And Allah knows best in all matters