My boyfriend doesn’t satisfy me

I’ve been with my boyfriend for 4 years and love him dearly. In the beginning of our relationship we would be intimate a few times a weeks, compared to maybe every 2 weeks now. I feel bad because my sex drive isn’t as high as it was years ago. When we do have sex now, it isn’t satisfying for me. I’ve been trying really hard to find different things to spice up our relationship but nothing is really working for me. His penis is smaller than what I was use to in past relationships but we made it work. He has ED due to uncontrolled blood pressure issues which I feel is part of the problem. I’m a spontaneous person and don’t like basically having to schedule sex with my boyfriend because he has to take medication just to help him get it up. I feel like I’m being insensitive but his blood pressure is what’s causing the ED. In the past I’ve brought up about how we should be healthier and work on losing weight together but it just started and arguments. He is insecure and just accused me of cheating on him with an ex. All together I’m just not interested in sex any more. I’m not sure how to approach this or even what do. Doesn’t anyone have any advice on how to approach this situation ?