Painful sex

I have a one and four year old and life is pretty busy. Me and my husband go through dry spells where we don’t have sex for a few weeks but then have frequent sex for a week or two. Sometimes sex can be painful at the beginning but as the lube starts working it is great. It hurts at the vulva area and I’ve read where thin tissue can cause it to be sore. When i even touch that area with my finger it is sore and doesn’t feel good. Has anyone had a similar experience and if so- what can help this? I don’t have an issue with lubrication especially when we use lube but when I read about this issue- lubrication to be the reason.