Hi there, vet Andrew here. What you describe is classic separation anxiety. If your partner has just moved in, Bruno may still be adjusting to the new environment, and this can take time. In the meantime, you can help reduce the problem by ensuring Bruno gets plenty of exercise - a good half-hour's walk so he's really panting. When he gets home, he will be worn out and less likely to focus on your partner's absence. Once he's settled from the walk, a few dog treats will also go a long way. Remember - Bruno has to get used to the new house and also to living with you. rewarding him with treats for good, settled behaviour will help. If you are really struggling, your vet can recommend anxiety relief medication, but this will only really be a temporary fix. Exercise and time are the key here - Bruno has to get used to the new 'pack'.
Please feel free to ask further questions here.