Thank you for your question and patience, I’m Tom and I’ll try to help you.
I assume that you spent some time on a tier 4 adult student visa until you married and obtained an EEA residence card presumably in 2012.
Basically, no one knows precisely what measures will be put in place should the UK leave the EU.
However, it is highly unlikely that your status in the UK will be at risk.
This is because there will likely be transityional measures if the UK votes to leave the EU which will allow you stay on your residence card at least until it expires. What the home office might say is that at the end of your residence card you must apply for confirmation of Permanent Residence, which is the right to stay in the UK without having to make any further applications.
So, they may require you to apply for PR in January 2017 but you will have to keep an eye on what happens. If the UK votes to stay in the EU then you can still apply for PR (it is best) but it would not be mandatory for you.
If you apply for PR then this means that you would have to apply and send your passport/documents off and because of the amount of people that will also be applying post-referendum it’s probably that you will have to be without your passport for 6 months or so.
Then you will have permanent residence confirmed in your passport. This means that you can stay permanently in the UK.
Once you have PR confirmed you can also apply for naturalisation (if you wish) as a UK citizen if you meet the following criteria:
My goal is to provide you with a good service. If you feel you have received anything less, please reply back as I am happy to address follow-up issues specifically relating to your question.