There's a lot going on. Firstly as you say there is the sadness that ex T was not able to provide this care, coupled with sadness that your mum was unable to provide this care to you. So there is a huge grieving process that will likely open grieving for what you didnt have. Also you've got the fact that what you desire is so simple and so easy to provide so there's a huge frustration that T couldn't do this for you.

Stuffing it down feels easy and comfortable but I would suggest sticking with t. These feelings for your T and even for your mum will eventually turn into some kind of healing. Your T sounds quite wonderful.