How to deal?

Have you every felt like you werent accepted into your partners family?

I've been with my partner since I was 18 (he was in his late 20s at the time). I met him while I was pregnant with someone else kid (who i wasnt with at the time). Something he knew about and chose to stay. We did long distance as he was a defence member and I was still in uni (decided to stay in the town i had mwt him in) at the time when we first started dating. We have been together going for going on 8 yrs, engaged and about to build our first home together (also planning a child together after our house is built). But the thing is I constantly feel as though his family think I am not good enough for him. I always feel like the outsider. Like when we used to lived closer to his extended family and he was away at the time (even though they didnt know) we where not invited to a party that the rest of his family was invited to. I have recently been told by his mother that my only motive for being with my partner is to marry him, divorce him and take all his money. She told me I was nothing but trash. And she loves nothing more but to tell anyone and everyone about me.

I have never felt comfortable or like I was welcomed into the family. I dont know what to do. I hate feeling like I am a piece of shit. I know that I am not because I am successful human being and I have my life together but it gets really hard to block out hurtful things especially in a family you already feel like the outsider in.

If you have been in this position before what did you do?