I have a major problem!!!

Hello community. I've been with my significant other for 2 years and we are now engaged. I love him dearly even with his stupid mood swings. We are sexually active, but here's the problem. It's only oral. I can't take it anymore!!! He has diabetes which robs him of an erection, and if he does achieve one it doesn't last long, and when he's inside I can barely feel it. He uses toys on me, but it's just not the same thing. I love him and I know telling him would hurt his feelings. I won't cheat, but I miss and desire it. What should I do????