danielb

Yes, you can do something about it. Having this type of martial problem is common nowadays and it is likely to be the reason for his previous relationship that he is acting like such a person.
Having to not pay attention to you and things going on in your life by your partner shows that he is not loyal at least he hasn’t been for a while.
Badmouthing you behind your back is equal to emotional abuse which can later turn on to be physical abuse. If you want this to be prevented I suggest you sit with him and make him talk this through and if that isn’t working out, I suggest you get medical help from relationship therapists(https://www.cognitivebehaviourtherapytoronto.com/areas-of-specialty/couples-therapy/) who is expert in handling such situations.
I hope you get through this situation you are going through.