Planning my own Baby Shower

Ok let me say first off, I DO NOT want to plan my own shower. Not even necessarily because I think it's improper etiquette (people should do whatever they feel comfortable doing) but because I just planned my own wedding in December in less than 90 days. The whole planning was incredibly stressful but luckily my DH was very involved in planning and it came together beautifully. My mom and sister now want to host a baby shower for me but they live 3-5 hours away so they want me to go scout out venues near me and get info on shower packages, etc. I told them that I really do not have the time or energy to do this now (I'm 27 weeks) but sent them a list of places that were recommended by friends or coworkers. Now they keep asking me to call and find out availability and how many guests we can have -- and they don't even have a guest list together. I just got very angry with them and again restated that if they wanted to throw a party then they would have to call. Or if it was too much effort they could just send the money they were planning to spend on a shower (about $2,500) to me and I would just purchase everything on my registry and send them back the difference. Now they are saying I am being an ungrateful brat because I am refusing to help them plan the shower. At this point, I just don't even care - I have enough money in savings to buy all of the items I need (although DH and I were earmarking it for a down payment on a house) so I dont really need a shower. But I feel like I am in a lose-lose situation here because if I don't help plan it they will continue to make me feel bad, but if I do plan it then I will have to deal with all the stress after I JUST got done with all the wedding planning stress. Any advice!?!?!