Hello Missy456,
Thankyou for your post and welcome.
Im so sorry to hear about your dog passing, that would have been very hard :(
The longer you don't speak, the harder it would be to reach out Since it has been 4 years already there is a lot of space between you. She is about to be a mother and I think this is a time that she needs her mother around the most.
Since she has resentment towards your new husband focus on building a relationship with your daughter without your new husband around, so just the two of you
I understand your feeling low but fixing your relationship and being in your grandchilds life could bring you great joy
In terms of how to reach out maybe send her a text message, take your time to write out something meaningful
Apologise for your absence, she may feel abandoned let her know that you love her and miss her and want to fix things, tell her you want to be in her and bubs life and tell her anything she needs you will do, then ask when is a good time to chat on the phone, Start with that :)