It does sound if there is a lot going on for you and that the gambling was a way of letting off some steam. It is how our brains get wired when we have been gambling for a while – so you are not pathetic or useless at all.
Now that your partner is no longer at the family home – does this leave you space to get some support? If you are in the UK you may be eligible for counselling support through Gamcare – https://www.gamcare.org.uk/get-support/our-treatment-offer/ or talk to your GP or local women’s aid for help with some of the other areas of your life. You can of course use the 1-2-1 here.
The important thing now is to put a full-stop behind the £1500 you have lost and not to try and chase your losses. Also not to think that because you have now gambled again – you may as well continue … these are all tricks that our “gambling mind” will try and tease us with. You went for several weeks without gambling so you know you can do it – just put the same barriers in place – each and every day. Please get support. I wish you well.