The lack of stamina definitely doesnt help. I very occasionally have lasted longer than 5 minutes but usually I am a minute man at best. I have great stamina when it comes to masturbation and can edge for a very long time but with actually fucking I am over and out before a kettle boils. My former wife told me she was not bothered if I came quick because when I have actually lasted longer it only enlongated the act and she said if I pumped away for a half hour it wouldnt make a difference because my penis is just way too small for her needs.
My girlfriend has no problem with it because she has other guys actually fucking her. ( I have a few times but it really is a pointless exercise especially since I get off seeing her get off) I have to admit I genuinely cum harder watching and edging than actually fucking. I love it when she sometimes looks over at me pulling on my tiny penis while another guy is floating her boat.