Supporting bereaved partner

My partner of 4 years has recently lost his dad completely unexpectedly.
At first he was coping well, and was grateful to have me around. But in the last week he has ended our relationship twice, and then changed his mind shortly after. I fully understand he is feeling lost and I can cope with him being distant. But this is obviously very very painful and stressful for me as well as I feel like I'm losing the most important person in my life.
I want to know how best to support someone who is pushing me away, so that when his grief has subsided and the loss is accepted, we still have a relationship and can pursue the life we have been planning for 4 years.

Hi. Hattie. Your partner is emotionally upset and anything he does or says will be coloured by those emotions. It's the grief talking. You can only support him and help by being there and giving him love, which he may badly need now. Try to be as patient as you can. It's so difficult for you to see someone you love in an emotional state. You will feel helpless, but try not to feel hopeless.
Emotions do quieten down, and it's then he will need love and support. There may be others on here who have been through a similar experience. I am sure you will get more replies. Now take care. Love can often find a way when we cant.
Blessings.