Sex life

Hey so me and my husband use to have a really good sex life. It got down after having my daughter but that was 3 years ago and i knew it was normal. We did get back on track. But lately past few months. I just never want to have sex with him. I dont know what it is. He is very sexually active towards me. Kissing me, touching me and would do it every night if i was up for it. He always shows me love and attention. But sometimes i just dont even like him touching me. I do feel really bad that i never want to as most of the time does. Any advice on this please ?