Answer #1: What changed the most is that I am now part of something much larger than myself: I am part of the Jewish People, for better and for worse. Honestly, nearly everything about my life changed, but not all at once. I am the same person I was before but my relationship to most of my world has changed dramatically.
Conversion to Judaism was like finding a lost part of myself, and it took time for all the pieces to come together -- really, they are still coming together, because Judaism well lived is a lifetime journey. Sure, my eating habits changed and my Saturdays are different, but the deeper changes came in the ways I relate to other people and even to myself.
Periodically something I read or a sermon I hear will cause me to examine the way in which I live a certain mitzvah. For instance, after hearing a sermon I decided that I needed to take better care of my body, which led to changes in my eating and exercise. I am a "conflict avoider" but I know I am commanded to make peace -- genuine peace, not fake peace! -- so I am much more likely to deal with problems than in the past.
I worry about different things: I am very careful not to embarrass anyone. That was not on my radar twenty years ago! All these changes have made me a happier person. I knew I wanted to be a Jew; I did not realize, going in, how much it would challenge me and how rewarding the changes would be.
I have received much, much more than I have given up, but in truth, there are some things that will always be a bit of an effort for me. (I miss pork -- ridiculous but true.)
However, I've never been sorry that I came home to Judaism, not for a moment.
Answer #2: I would say to this woman very seriously that her life will change no more and no less than she wants it to. Becoming Jewish is like coming home - it's not a matter of pushing yourself to look like someone else, it's a matter of growing so that you can look like *you*, so you can find that sweet spot where you are the person you know you were meant to be. I find that idea makes the superficial outside changes (will I keep kosher, will I cover my hair, what-have-you), so much less scary. Because *you* are in control, it's not change being forced on you. And it's not an on-off switch, your life can look as different or as similar as you want, and each day you can choose something new.
Answer #3: Since my conversion and bar mitzvah, my life has changed in several ways. I find myself thinking as if I have always been Jewish. I may not have the cultural experiences that born Jews have, but my soul seems Jewish to me. When I read passages from Torah, the stories are from my family history. Sarah is my mother. Abraham is my father. Israel is my home. I feel intimately connected to the stories. Before my conversion, I was a "ger". A stranger on the outside looking in. Also, when I look at life, I look at it from a Jewish perspective. "Oy" is an essential part of my personal vocabulary.
In my daily life, I attempt to keep as kosher as my life situation allows. I don't eat meat (from mammals) with dairy and I use separate plates when eating dairy. I find myself looking at what I eat and consciously deciding if it is "fit" for my consumption. I tend to lean towards the "eco-kosher" movement. Not only do I want to avoid eating things Torah doesn't permit, I want to support agricultural systems that are sustainable and humane.
Since my bar mitzvah, I have taken to wearing a kippah all the time--even at work. This has been the biggest impact in my life. It identifies me publicly as a Jew and thus makes me more conscious of my conduct. I want my actions to reflect positively upon the community. One wonderful thing about being visibly Jewish is that it invites curious people to learn about Judaism and its people. I see those invitations to be teachable moments where misunderstandings can be cleared up and people's horizons to be broadened. Even in my own family, my relatives ask questions about what it means to me to be Jewish. I wouldn't say that I'm perfectly Jewish, but I'm working on it.