<human>: We have been together for several months and they have been great. However my girlfriend has mentioned to me about her ex boyfriends and how she has a bad past with them. 

I just told her that I'm not them and that it's in the past, so we can move on. 

She has told me about one ex boyfriend in particular that she could not bring him to orgasm, and he could only do it while watching porn. She's told me this about 4 times. 

I snapped last night because I was trying to show her reddit, and how there is a sub reddit for everything she loves. Doctor Who,  FFA, music, stuff like that. 

And she automatically says to me that there is porn and erotica on here how her ex could only get off to that and not her and the like. 

This is the 5th time or so she's brought it up and she constantly tells me that "she's sorry and I'm not like any of her ex's but she feels this needs to be said" so I snapped on her and I told her that I feel as if she's comparing me to her ex ( she says she's not) and that she's not sorry about how she feels about it. 

It's subsided but now I permanently feel hurt. She says she'll be more careful in how she tells me things but I legitimately feel hurt,  like this isn't a 2 day thing.  is this normal?

Condense the text into a few key points
<bot>: my girlfriend is really straining our current relationship with her past and I feel very hurt. Am I overreacting?