My MIL tries hard to connect with me. Cook what she thinks I like, talk about what she thinks I like, offer ideas that she thinks I like. We are different and I don't mind different, just don't try to offer ideas and expect me to change. I don't do anything related to mother's day/grandmother's day, her bday or whatever day. I leave it up to my husband.
As for pictures, I will order them. A set will go to my mom, and a set will go to her but I give them to my husband to send by mail.
She drives me nuts because I'm not used to having my mom smother me as an adult and she drives my husband crazy. My mom had too many kids to focus on just one. My MIL has just one kid and everything is about her son, and now everything is about her grandson. My own mother doesn't interfere with how I teach my kids or at least she hasn't told me directly.

I would stop sending them. When I think people are going overboard sending me stuff, it makes me wonder what they want from me. For example: one of DH's aunts used to send us stuff all the time (same with the other SIL and her family). Both other SIL and I felt like it was extremely weird and like she was trying to force herself into our lives. I know it wasn't just me, b/c as I said, other SIL felt the same way. I just stopped acknowledging these things, even though it has been INGRAINED in me to write thank-you notes ALL THE TIME (if you knew me in real life, I am a fanatical thank-you note stickler) but I forced myself not to do this with her, and her gift-giving tapered off. Whew. This woman is very controlling and was using this to a) fill her life with activity (she has not much else to do) and b) get into our lives.

My MIL comes into the house and buys new or replaces random items of mine she's decided are not useful anymore. I don't like it but she's otherwise a great MIL and she means well, so I don't say anything. But I don't thank her. I just don't acknowledge it.

Why don't you ask her, during one of your normal interactions, whether she would still like to receive the photos etc. If she asks why, tell her that she never seems pleased to receive them so you are worried that you are doing something she may not like - taking up too much room or whatever. Tell her you would be happy to continue sending gifts because you love her but just want to be sure it's okay with her.

I found out, from my husband, that my MIL does not like to receive flowers (after I'd been sending them for about 3 years). She does a lot of sailing and is away for days so she felt it was a waste of money. I wasn't offended at all. Now I just ask her what she would like when there is a birthday coming up or make a mental note when she mentions something she would like.

Establish a different timeline, one that still keeps the door open, but one which will not cause you resentment.
- Mother's Day: Have your husband cover this w/flowers.
- Then how about 2 other times/year? Or whatever, just pick an interval. Send a few pictures. Put it on the calendar like a chore. Then don't think about it - really don't think about it -

Stop sending things. I give gifts because I hope that the recipient will like them. If they can't even be bothered to let me know that the gifts arrived, then they must not like them all that much, so why waste my time and money? I wouldn't care that she doesn't send a formal note or anything like that, but not even mentioning that she received them when you or your husband talk to her? Not cool. Send cards for regular holidays and the kids' school pictures, and drop the rest.

I think it's too much to say she doesn't care. You can ask her if she doesn't want to get them, but some people have trouble expressing thanks and you can't assume she dislikes them just based on that alone.

I'd stop sending gifts but continue to include her in the photo distribution list since all the grandparents get that, right?

Well, that's definitely rude, but it's not really in the spirit of gift giving to get mad just because she didn't say thank you. She's got some weird issue, that's obvious, but does it have to be your weird issue too? Maybe you can just ask her "Larla, do you like getting little photos of the kids and stuff? I can stop sending them if they're cluttering your house." Some people actually don't like gifts. I usually don't want gifts from people, but I summon up the decency to say thank you. And if she does like them, I would keep sending her mementos of the kids. Grandparents usually love that stuff, some people are just insanely awkward.

I'd stop sending, for sure. If you don't appreciate it, I see no reason to waste my time/money/effort.

My MIL never acknowledges any gifts. I have gone out of my way to send pictures of our kids, cards, flowers, but she never says a word. DH asks her if she has receives these items, and she simply says yes. She doesn't say thank you or show any appreciation. I'm planning to stop sending anything. It makes me sad, as I feel I am doing something spiteful agains someone in my family. However, I can't justify the time and effort spent on sending her things when she apparently doesn't care. Has anyone experienced anything like this? Thanks!