Hey T., I went through that same exact same thing w/ my L.o. she was 3 1/2 also, and would get up for anything and everything.
one night I was jut sooo tired and was just done w/ her waking me up to go potty when she didn't have to, or to come crawl in bed w/ me, and thrash everyhere... I Just got finished watching an episode of super nanny, LOL. I really do like her, and the couples osn had a similar prob. and he was 2. I figured If it could work for him I could try it.. That night about 3 hours before bed, I cut off all her drinks, snacks, ect... made sure she went potty right before she went to bed, and explain how If she needed to go potty in the night, there was a potty chair right by her bed, (just in case) and to go potty on it if she had to go, and to not wake me up because shes a big girl and can do it by herslef. But if she didnt have to go potty, she needed to stay in bed and sleep, and not to get up and crawl in bed w/ me, but even if she does she hjhas to come right back in her room and sleep in her own bed cuz shes a big girl and cannot sleep w/ mommy at night any more. The same goes for anything else, and If she does get out of bed except to go potty, then go right back into bed, she will have to go right back into bed. Then when she got up that night, she came in, and asked to go potty. I Told her she ws a big girl, If she needed to, there was a little potty in her her room, and that I'm not going to help her so go potty byherslef like a biggirl, then go back to bed. She decided to scream and cry at that, then try to get back in bed w/ us. I said no maddy, remember what I said b4 we went to bed? If you get up, that u were going to go right back in bed, and u couldnt sleep w/ me at night time. Then grabed her hand and said come on lets go back to bed. She then threw herslef down, and started crying again. I picked her up, didnt look or talk at her and put her in bed, and coverd her p, and left. 10 min. later she came back, I grabed her hand, didnt look at her or talk to her again, then led her back to bed. I did this like 5 times a night for 2 weeks, then she finally stopped. It did dut down to like 2c after 3 days, then once a night after 7 days. I worked wonders for me.