I don't usually frequent this forum of adisc, but i saw your thread from the recent list.
First off, you are who you want to be. Being AB doesn't mean you need to be a specific category. You don't even have to say that you are an AB if you want, but it does make for a convenient way of explaining yourself. There isn't a club membership that says you have to live by certain rules and rights, being AB, or Furry, or sissy, includes usually one or two specific themes that are common to the rest, and then a bunch of personality traits that customize that title to yourself.
AB: usually means you like to feel like a baby, which can include liking diapers or babyish things.
Furry: usually means you like anthropomorphic characters. To what depth of liking them is up to you, this may mean that you'd like to be one, or it might mean you like to read comics with them.
Sissy: from my understanding means that you like to be more feminine from a younger age aspect. For example, princes things and pink. To what extent you like those, is also up to you. Weather you like to have princess posters on your wall, or if you like to wear princess print underwear, or wear frilly dresses.
You can say you are part of that category if you want, or you can say that you don't feel like that category describes you well because of certain elements of it. For instance, I don't consider myself a sissy, at least yet, but I have a "hello kitty" diaper, a pink diaper with bunnies, and a MLP diaper, but I still don't consider myself a sissy, mostly because I just think they are cute, but from a childish standpoint rather than a feminine childish standpoint.
Some people might say, "well, you must be a sissy then because you like pink," and if that is what they want to think, then let them, you cant control them. If they want to know what you think though, then define it yourself, you can say, "I like pink, but I don't consider myself a sissy because I don't like some of the other stuff," or, what is more likely based on what you have said, "I like a lot of sissy stuff, but not all of the time, I guess you could say i'm a part time sissy."
The Adult Baby lifestyle can sometimes be complicated because we are forced to embrace two identities, which then can split into more identities because we are used to changing between two. We don't have multiple personality disorder, because we can control it, and we don't loose recognition of our other personalities, but we do have a more defined separation of public and private personality than some people do. Sometimes it is easiest to refer to yourself as your "little side" and your "adult side," to which you can also split into other categories if you feel inclined. You could say that you have a "little-sissy" side, and a "little-furry" side, and sometimes they collide together. You could also say that you have a "adult-furry" side, which wouldn't commonly collide with your little side unless you were talking about sexuality aspects.
Separation of personalities isn't uncommon. People may say, "I need to put on my poker face," at which point they become absolute liars, but before hand, they could be the most honest person you know. Being a human isn't a simple thing, and there isn't a simple solution for categorizing a person for 100% of his/her existence. One day you might want to eat cereal for breakfast, the next day you would much rather have bacon and eggs. Try to think of yourself as a Venn-diagram rather than a single circle of things.
As for the Christian aspect and your dating aspect of the conversation:
I used to consider myself Christian, but my views have changed, however, i'll try and approach from your point of view. I believe that if Jesus was willing to sit with the sinners (not saying that any of these aspects of your life are a sin, but if you believe that), then he would be willing to sit with you as your AB-furry-sissy self. Humanity is really a beautiful thing because it isn't about all of us becoming clones of Jesus, it is about how Jesus saved imperfect creatures who were not like him, who were different in many ways, and rather than see them be destroyed, he preserved them. People might say, "Well Jesus commanded to be perfect." True, but I don't think it means to be perfect in everything, because that is impossible for humans, it means to be perfect in your love and respect towards others, that is why the verse with that commandment starts with the context of "I say unto you, Love your enemies, bless them that curse you, do good to them that hate you, and pray for them which despitefully use you, and persecute you..." So in other words, love the fact that we are different, and don't just pretend that you do, be perfect in loving other people and respecting their differences, and their struggles.
As for dating life:
I'd say, you can try online, but I personally don't think i'm going to do well that way. You are probably best off looking for somebody that fits your personality (introverted/extroverted, clean/sloppy, intellectual/goof, fitness/potato, and so forth). Once you find somebody like that, be sure to address your needs that you can not do without having him/her accept and love before you both become too intimate. To me, that means, before we become exclusive, I need to tell my partner about my little side, and make sure they are happy with me being that way, at least after a little bit of time.
Best of luck, and sorry this is so long.