My anger really helped me. I channeled it - it got me through preparing the house for sale, selling it, buying my own place, getting divorced etc. My anger motivated me and often shielded me from backpedalling. I kinda miss its motivating power now!
For me, anger was very useful. I wasn't 'supposed' to get angry nor was I 'supposed' to show it. Learning how to get it out, how to use it wasn't easy but it really helped. Counselling also helped me control it.
I hope that you too can work out how to use your anger productively instead of having it all bottled up. From your post, it sounds like your anger has resurfaced at your RABF's admission and that you had a lot of anger already stored up. Have you been to counselling? It helped me realise that I'm 'allowed' to be angry. And what to do with it!