Hi-- I'm sorry you're tired. . . you sound like a sensitive, responsive mom and soon you will be rested again. ;) You might be interested to know that the American Academy of Pediatrics recommends that all babies be breastfed until they are at least 12 months old. You'll easily meet that guideline, but there are many strategies to weaning your baby only at night, since it sounds like it's the nighttime nursings that are really getting you down. The simplest one is "don't offer, don't refuse," which is gentle and still encourages your close relationship but also allows you to find other ways to meet your child's needs beyond breastfeeding. With my kids, I've had my husband offer a fun and filling late-evening snack to help stave off the nighttime hungries. Then, if they woke up at night, he or I would try a few other things (rocking, patting, snuggling, a drink of water) before nursing. This was not a quick-fix, but after a couple of weeks of a good snack and a change in the nighttime response we were sleeping for a much longer block at night.
Sometimes it's not the actual calories they need as much as it is some human contact and reassurance, and I personally don't think that's a crime. I mean, they are still babies, learning to trust, and I much prefer my children to connect with other people than with inanimate objects for comfort. I just can't see how responding to your baby's needs is a bad habit. . . . You could try some negotiation techniques, like saying goodnight to everything, including nursing, until the sun is up again. (In my experience, bargaining works better with a slightly older toddler, but anything's worth a try when you're wiped out!) In my opinion, any kind of cry-it-out method will just leave you with a stressed, clingy, ultra-needy child who *really* wants to nurse for reassurance and won't be easily distracted from it during the day--could throw off your whole weaning strategy.
You also might be interested to know that sleep researchers define "sleeping through the night" as a four to five-hour stretch. Adults wake at night, too.
Bottles at this point just sound like extra dishes to wash to me, and the introduction of something that will be hard to get rid of later. Consider a straw cup, and maybe adding extra calories to solid meals instead of formula. Guacamole and refried beans are favorites at my house for stick-with-you toddler foods. Hummus, too. Human milk is so, so sweet that the substitute will be a hard sell for someone who's been used to the real deal. I have read that since the action of drinking from a bottle is so different from breastfeeding, many babies who use bottles have more orthodontic and mouth/palate shape formation issues that babies who exclusively nurse, so choosing a cup or a straw-cup seems like a healthier choice than going to a bottle at this point. Offering a fun cup at mealtimes would be appealing to be like the B. people--maybe with water and ice cubes in interesting shapes, or made with fruit juice? I've seen cute ice tray at kitchen shops.
You might enjoy the books "How Weaning Happens" and also "The No-Cry Sleep Solution." They both talk about night-weaning and complete weaning strategies that are not miserable for everyone. Gradual weaning will help you stay comfortable, too. It's hard to sleep when you have a toddler whoneeds you, but it's also hard to sleep when you're engorged and end up with mastitis, too, so excellent self-care is important.
Perhaps in a couple weeks your baby will graduate to a new and different need and some of the nighttime neediness will fade. The nighttime needs could be a call for more snuggles, or just more calories during a growth spurt. Hang in there--this too shall pass!