OP, I would suggest you put all thoughts of gifts from your family, what gifts MIL has given her family and all financial issues out of your mind. The main problem here seems to be the total lack of communication between both of you and it sounds like some positive moves towards your MIL to bring her 'into' the experience of your pregnancy is what's needed.
I am a grandparent/MIL and I usually wait for her to invite me into the areas of her life that she wants to involve me in. I don't want her to feel as if I'm trying to take over anything in her life because she happens to be married to my son and I respect her and her personal space. Most importantly she's a really lovely woman who loves my son and makes him happy. She does contact me when she needs something and each time I've helped her out (when I can, I can't always do what she asks) I always say bye bye and remind her to ask anytime . I asked a couple of times if I could do something in the early days and could sense it made her feel awkward so I learned from that, hence now waiting for DIL to ask.
If my DIL and son had broken up and got back together again I would wait for a sign from my DIL that she was happy for me to be in contact with her again rather than force myself into her life.
Maybe send her a text, saying it's been a while since you've chatted, it would be great to catch up and when would be a good time to have a call? Depending on how upset her son was during your rough patch she may still be trying to come to terms with the fact you are back together and having a baby. These things can't be hurried up, sometimes people just need time and as much flack as MILs get they are human and still having feelings. One day you will be a MIL maybe, so treat her as you would want to be treated.
Don't forget that every relationship is different and people are not obliged to treat each other in a particular manner just because of the role they hold in a family tree. If your MIL feels closer to her daughters then you can't hold a grudge about that. I know I treat my daughters differently to my DIL in relation to how much money and time I spend BUT my DILs mother also favours her daughter over my son - it's perfectly natural and does not infer any malice.
Good luck.
P.s.: the gifts thing, your family are very generous but no way would I allow my mother to pay something up over weeks or months for a baby that I was having. If she can't afford it then you should pay for it, regardless of her insistence.