Baby cries all day long

My baby will be 9 months on the 15th and she is crawling and standing up with support, but she still cries if I try to leave the room or even stand up from sitting with her on the carpet. I stay home with her so I don’t work I don’t leave her with anyone it’s only my husband and I living in the house with the baby. I know people suggested letting her cry it out, but that doesn’t help I let her cry for like 2-3 minutes and then I start to feel guilty for letting her cry and she even cries harder. Help me mom please because I’m planning to go back to work when the baby is one I’m gonna have to leave her with my mom or the baby sitter while I work but she’s super attached to me. And she wakes up like 4-5 times each night to take a bottle she only drink 4 ounces each feeding what can I do to so she will drink at least 6-7 oz. please and thank you 🤗🤗🤗🤗🤗🤗🤗