Originally Posted by Gatling
By the sounds of it you will likely need separate housing applications your parents on one and you on the other if your an adult ,
I had a very similar thought while pondering this situation. what's more, if the OP is now in college, they may be deemed as not having a housing need if they are able to pay €500/month rent-equivalent at the moment. However if it could be shown that they need to live in the house to care for a sick parent, that could change things.
My first question would be: what is the parents plan for dealing with the situation, and indeed for housing themselves once the mother retires. They may well have a plan (eg using savings) that hasn't been shared with the OP as yet, and may not regarded it as the OP's business, even. Some families won't see it that way, but some definitely will.
Next: what income is the mother earning? We don't actually even know if they meet the social housing criteria - though obviously they will short term while she recovers from the surgery. (Have the doctors given any indication of how long recovery is likely to take? Since the mother has been working, she will most likely qualify for Illness Benefit, and will get a qualified-adult payment for the father, too. Whether or not there's a top-up for the OP depends on his/her age, I think.
Who can help? Citizen's Information is one obvious port of call. They have information about benefit rates and approaches. Threshold may have a local office. Vincent de Paul also help with cash / food sometimes. It is worth approaching local voluntary housing associations (Clúid, Respond, etc) - many of their properties are let via the council - but some aren't. Make sure that you have information about the mother's disability, because there are council / social houses which are available to older/disabled which aren't available to others.