Contribution based getting inheritance

hi there
i just need advice, i am currently unable to work due to three conditions which leaves me in chronic pain, neurological disorders and fatigue and needing daily help. i am in Support Contribution based ESA with DLA. i am married and my husband works but up until i fell ill in 2007 worked since i was 18 so paid more than enough NI contributions. my father recently died and is leaving me and my two siblings money around £20,000 or more each. where do i stand with losing my benefit etc. i read that i will lose my main benefit due to the inheritance so i said id put it all to paying off our debts such as house repairs, new boiler which is needed, student loan, catalogue, and the rest to the mortgage but again what is the rules about that as i know there is also a thing in place that states its still classed as an asset and does not matter that there is no money gained we still have that asset.
i am so confused and stressed about this

thank you so much for replying , i was so stressed with this money, i know my dad would have been upset knowing everything he had worked so hard for to leave us has caused this. i feel a bit less stressed and will do as you suggested and make memories from it. i will pay off a lot of debt which will help us as well. i had even suggested giving the money to a charity but they said if i did it would still be classed as me giving away money that i could live on. i feel so sad for those which are trying to do the right thing and leave thier family money for it to be eaten up with inheritance tax and everything else. thanks so much for replying

thanks so much for getting back to me
it was much appreciated
debs