Our family had been a concussion of different faiths, people from different states within India and different countries. So it was never a problem and I may not be able to explain this scenario at the other spectrum properly. If you are a smoker, you can think about how you have the pleasure for your senses while living with a strictly non smoking family. ( I don't know if this is example )
But generally, among Hindu community, there is a high tolerance level, with respect to others belief systems, because all paths lead to GOD. Hindus don't have a fear that if you participate in any other religious practices, you will go to hell or that if you abstain you will rot in hell. There will be enough and more square foot of personal space where you can just do whatever you want.
If you have a belief system, respect others belief system also. Participate in them, explore them and be a seeker. Certain ceremonies will require you dress in a certain fashion. Get along just like you will join your friends in a new game and follow those rules during the game. There could be dietery restrictive period of year like "Lent " before Easter and Ramadan. I fast totally without water for twice a month on the days called "Ekadasi" for about 36 hours. It has health benefits - whereby the Nobel Prize last year on Autophagy recommends fasting.
You might have heard that there are millions of Gods in Hindu religion. It is wrong, there is only ONE GOD, anything that you can describe and can be made into an idol is Demi God, even though they are called as God, while speaking. So, within a house, there could be someone who follow the female deity form " Devi ", while another person go to a temple of Lord Siva, While another person try to befriend, Lord Ganesha ( with elephant face), and yet another follow Lord Vishnu. So if you really put effort, you can find a Million Hindus who worship different forms / manifestation of GOD. As told in my last post, Devi herself is worshipped in 9 forms, from a motherly to most destructive in the coming nine days.
Now, I can only narrate my own personal experience in my family. My sister is nearly 10 years elder to me. She was married to a person whose family was strict vegetarian. So she used to be vegetarian in her home, but come to our place to eat non vegetarian. Now she has become vegetarian, she subtly tells me to be vegetarian, whereby I still eat Beef, Pork and also anything that comes to devour me. I enjoy cooking a spectrum of dishes, and don't mind having raw non vegetarian like Sushi, etc. Her daughter is currently studying in Copenhagen University, Denmark, who is a non vegetarian.
Beef could be a big NO, NO, for a large group of Hindus. When I go to those places, I am just contended with what is available there. I feel like eating, I get it and eat within my own home or my own room for that matter. If I find a partner who is vegetarian, may be she will never cook for me anything non vegetarian. May be, I will end up buying a tiny fridge for myself. . Nothing escapes me.
Now, when we have parties, there is always a Vegetarian corner, if muslim friends are attending, out of respect for them, we will avoid pork dishes, OR have a separate corner for Pork. ( There could be some houses, certain food preferences need to be your little secret with your partner )
I have to say that it will all depend on case to case basis, and on the mind set of that particular families. I think you can ask your partner about what is the scenario in his place and come to an arrangement with him early. You can ask him, if daily worship of the Gods are done and is it mandatory that all members have to attend or not. I feel that as long as you get along and don't scorn upon and show your displeasures in the open and have an intolerant mentality inside, any Hindu Household, would be of no issue for anyone from another faith.
