Yes, in essence it would end up between 50/50 and possibly even entirely your fault.
A slightly different scenario but it helps highlight the legalities of junctions when driving.
I was a passenger in my friend’s car when the car in front indicated left at a side street but stopped halfway into the junction. My friend hit this car as the driver stopped with nothing in front of her (it seems to let her passenger out). My buddy refused to accept liability and was adamant she should not have stopped at all and it went to insurance. The outcome was 100% her fault for the very reasons you can imagine.
The Highway Code is full of “MUST” statements that you must stop at junctions to give way to all traffic. What you (and I did in my example) was 100% illegal. PERIOD.