Income related ESA Support group: Relationship Breakdown

Hey so i was hoping to get some advice regarding where i will stand finacially,

so up until a few years ago i was living alone in my council rented property in receipt of housing benefit and council tax benefit, in receipt of Income Related ESA in the Support Group receving a severe disability premium along side the standard esa disability premium too, while also being in receipt of PIP at both Enhanced rates, so in total my fornightly amount was around £397 every 2 weeks for ESA 

a few years ago i got into a relationship and my partner subseqently moved in shortly after, my partner isn't disabled but was added onto my ESA claim so i lost my severe disability premium so i reported the changes to ESA and also had to report the change across the housing benefit and council tax to which both ESA and Housing benefit sent out a change of circumstances form which were filled in which then lead to,
my current finacial situation,

 living with partner in receipt of Income Related ESA support group claiming housing benefit and council tax benefit (partners name jointly appearing on council tax bill) but not on housing benefit one? in receipt of PIP at both enhanced rates, and partner claims Carers allowance for me as my full time carer - he is not in employment, 

current ESA entitlement is around £312 every 2 weeks, along with carers weekly

Unfortunately my relationship is severely suffering and isn't working out due to finacial struggles amongst many other reasons and is making me very depressed,
and i'm seriously considering ending things my only fears are what will happen to me on a finacial scale if i do, so hypothetically speaking

upon informing ESA that i've had a relationship breakdown and i now live alone again and i've stopped my then ex partner from claiming carers allowance for me 

and also informing housing benefit and council tax benefit that i now live alone again 

what would happen, would i be able to remain on my Income Related ESA support group and be able to essentially reclaim my Severe disability premium that i lost when he moved in? meaning i'd be on the same rate i used to be of around £397 every 2 weeks?

and with informing housing benefit & council tax will they be able to put things back to how they used to be? 

or would this be such a change that would initiate the requirement to be switched over to Universal Credit? i'm just hoping i can get things changed back to how they used to be prior to having a partner, as i fear a swith over to universal credit will really put me into a bad finacial situation itself,

any advice and support is greatly appreciated thank you in advanced.