Vaginal tearing & Irritation After Sex

I’ve been with my boyfriend for over 5 years now, and nearly every time we have sex the skin around my vagina gets irritated and itchy, and the back side of my vagina (or perineum I guess) tears. I don’t think it always used to happen, maybe just the past few years or so. Sometimes it will feel irritated during sex, but even when it doesn’t, it will still be irritated after so that the next time we go to have sex it’s uncomfortable. We have always used lube, we used to use KY Jelly and I thought it worked great but then I started getting fed up with this happening more and more, so we switched to Ah! Yes water based lube. Both my partner and I have tried different shaving routines/schedules around sex and nothing seems to work. I am 23 and I’ve been on the same hormonal birth control pills for the last 7 years or so. I always pee after sex, and only ever use water to clean down there. Any advice would be appreciated!!