So sorry for what you are going through Victoria.
I agree with the others that stress will massively affect your BG's & that in return will cause you stress so maybe can you (for now) accept that your BG's will be higher for a while but know they will get better when things improve all round?
In the meantime, do all anti-depressants raise BG's? There are lots of different ones & they can be very helpful in the short term, maybe you or the GP could try & find out?
I wish you luck with the Tresiba, £25 over 5 months is miniscule. I think sometimes they don't put much thought into what they are actually saying. Thank goodness for this GP.