Thanks Wabisabi for the positive feedback!
Obieone, I, too, am wondering how things worked out for Dsis, if you don't mind telling us.
Rosyglow, so sorry for your worry and heartache! But glad you came here before any overall break cuz maybe we can help you forestall one (can't promise anything, of course).
I'm sorry that DIL has never been open to being friendly with you. Some DILs are like that though, happy with their own friends and relatives (as well as their DH and kids, of course) and just not into getting close to their MIL. It doesn't necessarily mean there's a specific problem. IMO, it was very wise of you to accept the situation.
Her reluctance to let you so much as "push the buggy" when they visited is a red flag, I agree. But it may not mean very much, after all. I don't know what people call it in the UK, but here in the States, where I am, we often speak of the "inner Mame Bear." A lot of moms seem to be very protective of their babies on instinct, keeping others somewhat at bay, except for the dad or maybe people they know really well. If this was the case with DIL, it probably was nothing personal, even though it felt that way.
I hope you didn't push the issue at the time though I know it may have been hard not to. If you did, that may be why, sorry to say, DIL is avoiding you now. If not, then it may still just be a matter of the distance. Am I right in guessing that GD doesn't come with him either? They may both just find that traveling with a little one is too hard. I've seen a lot of DILs and DDs complain about that kind of thing on other sites. I'm sorry that means you've only seen GD twice in all this time. But chances are, if you don't press the issue, that will increase.
It's a good sign that DS contacts you so often! I've read (again on other sites) that some young couples have a yours/mine policy, where he contacts his side of the family and she hers. That means the thank yous and so on would be up to him, too (if that's what they're doing), so he may just be remiss about this. Be prepared but there are probably no real worries here.