Hi Gustav,
sorry to hear about your relapse, don’t beat yourself on it I know it is easier be said than done, but now you have these catastrophizing feelings of hopelessness and insecurity about the future and all these bad feelings that you got in the first few days after the relapse, just hang on, this is just a temporary feeling and will fade away mostly within the 1st week.
the only thing that you can do is to start over, learn from this relapse, ask yourself what went wrong, and try to fix that.
and to make it simple it is all about access to money, as I remember you already informed your partner about this addiction, then just give her financial control, this will guarantee that you will not have enough money to relapse.
and look to the positive side you managed to stay gambling free for 72 Days it is a good achievement you should be proud of yourself. you can do it again and you can do more this time.